Volume 25, No. 2 (June, 2024)
1. PAIMAN*, ZULKAISI NURUL AMAR, IKHSAN FIRMANSYAH, HAGENG RAHMATULLOH PRIYO PAMBUDI, ANGGUNILA, CICILIA TRI KUSUMASTUTI AND ARDIYANTA [Optimizing bioherbicide application timing and plant spacing to manage weed growth in rice (Oryza sativa L.) cultivation]. Research on Crops 25 (2): 207-215 (2024). Department of Agrotechnology, Faculty of Agriculture Universitas PGRI Yogyakarta, Yogyakarta 55182, Indonesia *(e-mail: paiman@upy.ac.id)
ABSTRACT
Weed management is crucial for successful rice cultivation. Bioherbicides derived from cogon grass extract offer a promising solution for weed control. Additionally, optimizing plant spacing has been recognized as an effective method to suppress weed growth. Thus, this study aims to investigate the impact of cogon grass extract application timing and plant spacing on weed growth in rice cultivation. The study was conducted from October 2022 to February 2023 in the Special Region of Yogyakarta, Indonesia. The study was 3 × 2 factorial and arranged in a randomized completely block design (RCBD). The first factor was the bioherbicide application timing: control (no application), three days before planting, and at the time of planting. The second factor was plant spacing: 15 × 15 and 25 × 25 cm. In total, there were six treatment combinations and three replications (replications as blocks). The research results indicated the application timing of bioherbicide did not significant effect on the growth of weed and rice, as well as the grain dry weight. Fimbristylis miliacea was obtained as the dominant weed species. Bioherbicide application at the time of planting could alter the composition of weed species compared to the control in plant spacing of 15 × 15 cm. Furthermore, the plant spacing of 25 × 25 cm resulted in higher grain and weed dry weight (19.40 g/clump and 45.00 g/0.25 m2) compared to 15 × 15 cm (12.92 g/clump and 23.04 g/0.25 m2). On the contrary, the grain dry weight per hectare was higher in 15 × 15 cm (5.74 t/ha) than in 25 × 25 cm (3.10 t/ha). The research findings indicate that closer plant spacing can suppress weed growth and increase the grain dry weight per hectare compared to wider plant spacing. We recommend that the use of cogon grass extract dosage needs to be increased above 50 L/ha.
2. T. D. H. TRUONG, T. D. TRAN, Q. C. NGUYEN, T. T. D. NGUYEN AND T. T. H. HOANG* [Enhancing the efficacy of biochar derived from crop residues on rice (Oryza sativa L.) dry matter, yield accumulation and soil organic carbon in Central Vietnam]. Research on Crops 25 (2): 216-221 (2024). University of Agriculture and Forestry, Hue University, Hue City, Vietnam *(e-mail: htthoa@hueuni.edu.vn)
ABSTRACT
Biochar from crop residues plays an important role in reclamation of degraded rice soil due to imbalance fertilizer application and soil carbon sequestration. The objective of this study aimed to evaluate the best type and rate of biochar application for rice dry matter and soil organic carbon improvement. Therefore, pot experiments were carried out in two seasons of spring and summer 2023 at the University of Agriculture and Forestry, Hue University. Twelve treatments including 2 types of biochar (rice husk and peanut shell) and 6 application rates (0, 1, 2, 3, 4, 5%) were used and arranged in a randomized block design with three replications. Research results showed that the shoot dry matter was higher 9.5-27.0% (spring season) and 19.1-26.9% (summer season) at a rate of 5% application in both types of biochar than control. Rice husk biochar application had higher shoot dry matter than peanut shell biochar application in the same application rate from 0.30-0.46 g/plant in both seasons. Similarly, organic carbon was found the highest content (2.15-2.21%) when the application of biochar from crop residues at a rate of 5%. Biochar from crop residues is considered as a good amendment for increasing crop dry matter and soil organic carbon.
3. T. X. P. TRAN AND D. H. TRAN* [Impact of rice straw biochar and reduced chemical fertilizer on the growth and yield of rice (Oryza sativa L.) in Central Vietnam]. Research on Crops 25 (2): 222-227 (2024). University of Agriculture and Forestry Hue University, 102 Phung Hung Street, Hue City, Vietnam *(e-mail: tdanghoa@hueuni.edu.vn)
ABSTRACT
One way to effectively use rice straw without causing environmental pollution is to produce biochar and reuse it to improve rice yield and soil properties. Using rice straw biochar has increased rice productivity and can reduce chemical fertilizers. Therefore, this study aimed to evaluate the effects of rice straw biochar application with reduced chemical fertilizer on the growth and yield of rice at Quang Phu commune, Quang Dien district, Thua Thien Hue province, Vietnam with four treatments of the co-application of rice straw biochar doses of 5, 7.5 and 10 t/ha and chemical fertilizers of 75, 50 and 25% of the recommended dose. Growth parameters, yield components, yield of rice, and soil property were investigated. The results showed that the rice straw biochar had a positive effect on the growth, yield of rice, and soil properties. The co-application of rice straw biochar of the level of 10 t/ha and chemical fertilizer of 25% of the recommended dose was optimal levels produced the highest growth and yield (63 t/ ha). The co-application of rice straw biochar and chemical fertilizers increased organic matter, improved both soil physical and chemical properties, and reduced chemical fertilizer use. As a result, the rice straw biochar may be recommended to farmers to apply for rice production.
4. Sunita Meher, Sanjoy Saha*, Nitish Tiwari, Ashirbachan Mahapatra, Jagadish Jena and Minu Mohan [Efficacy of broad-spectrum herbicide mixtures on weed flora in wet direct seeded rice (Oryza sativa L.) in the east coast plain region of India]. Research on Crops 25 (2): 228-234 (2024). MSSSoA, Centurion University of Technology and Management Paralakhemundi, Odisha-761211, India *(e-mail: correspondingauthor123@gmail.com)
ABSTRACT
Wet direct seeded rice (DSR) attributing floristically diverse weed flora which emerges as main constraints for its successful cultivation. Broad spectrum herbicide mixtures can be acted as weapon for mitigating this issue by nullifying the challenges like weed shift, herbicide resistance etc. Consequently, an experiment was conducted at the Institute Research Farm of ICAR-National Rice Research Institute, Cuttack, situated in the east coast plain region of India specifically in mid-central table land agro-climatic zone of Odisha during the Kharif seasons of 2020 and 2021 to assess the effectiveness of different herbicide mixtures in managing weeds successfully. The experiment was laid out in Randomized Complete Block Design encompassing 12 treatments, viz., nine post-emergence herbicide mixtures (experimental combinations for testing), one post-emergence herbicide check, one weed-free (T11) (weed-free plots were maintained by hand weeding) and one weedy check (T12), replicated thrice. The net plot size was 5.8 × 3.8 m (22.04 m2). The test variety CR Dhan 203 was sown in 20 cm rows apart. Weed-free treatment (T11) was at par with fenoxaprop-p ethyl 6.7% EC (w/w) + ethoxysulfuron 15% WDG (w/w) (50+15) g/ha (T4), penoxsulam 21.7% SC+ cyhalofop-butyl 12% EC (w/v) (25+100) g/ha (T3) , azimsulfuron 50% DF+ bispyribac sodium 10% SC (22+25) g/ha (T1), flucetosulfuron 10% WDG (w/w) + bispyribac sodium 10% SC (25+25) g/ha (T2) , bispyribac sodium 10% SC + ethoxysulfuron 15% WDG (w/w) (25+15) g/ha (T5) for high performance in terms of grain yield. Also showed lowest weed flora dynamics and relative weed density as well. Among the herbicide treatments, fenoxaprop-p ethyl 6.7% EC (w/w) + ethoxysulfuron 15% WDG (w/w) (50+15) g/ha (T4) registered the highest weed control efficiency (86.49%) and lowest weed index (6.69%), hence demonstrating as most viable and adoptable combinations for agricultural crop production.
5. M. Jayaraj, R. Durai Singh*, T. Ragavan, Syed Abul Hassan Hussainy, P. Subramanian, B. Bhakiyathu Saliha and B. Sivasankari [Influence of establishment methods and seed coating techniques on the performance of direct seeded rice (Oryza sativa L.) under Periyar Vaigai command area of Tamil Nadu]. Research on Crops 25 (2): 235-240 (2024). Department of Agronomy, Agricultural College & Research Institute TNAU, Madurai-625 104 (Tamil Nadu), India *(e-mail: duraisingh@tnau.ac.in)
ABSTRACT
Rice is a crucial staple crop cultivated extensively in command areas worldwide. In the command areas, the release of water varies due to the inadequate amount of rainfall in the source area and its proper supply. To combat such situations, direct seeding (DS) methods can be opted for; however, lacunae like excess seeds per drop, scattering of seeds, and intercultural operations like thinning, gap filling, and excess weed growth need a clear refinement to enhance the profitability of rice cultivation. Therefore, a research trial was conducted during 2022-24 at Central Farm, Agricultural College & Research Institute, Madurai, to evolve a suitable direct seeding method. The present investigation was laid out under a split-plot design comprising four main plot treatments and four subplot treatments replicated thrice. The main plot treatments comprised different seeding methods (S) and the subplot treatments comprised different seed coating techniques (P). Based on the experimental results, paper roll seeding and DS + Seed coating @ 2% KNO3 fb Bacillus sp. and Azospirillum (PR + P-KN) combination performed better on establishment with grain (6150 kg/ha) and straw yield (7824 kg/ha) respectively. Regarding the B:C ratio, OS-GP + P-KN resulted in higher with 2.64, closely followed by PR + P-KN with 2.61. The least effect was recorded in the combination of round slots in rice drum seeder and dry seeding (RS + DS). Investigating different techniques of direct seeding and seed coating is essential across various regions, particularly in regulated areas where water discharge remains unpredictable.
6. Victoria Vladimirovna Ustinova* and Alexey Dmitrievich Timoshkin [Environmental surveillance of the rice massif in the Kuban-Protoka river region]. Research on Crops 25 (2): 241-246 (2024). Federal Scientific Center for Agroecology Integrated Land Reclamation and Protective Afforestationof the Russian Academy of Sciences Volgograd, Russian Federation *(e-mail: ustinova-v@vfanc.ru)
ABSTRACT
The article presents the results of environmental monitoring of the rice massif between the Kuban-Protoka rivers. The analysis of the dynamics of the yield of rice crops grown in the zone of risky agriculture, namely in the territory subject to secondary salinization, is carried out. Based on the results of chemical analyses of water and soil, methods of increasing fertility on degraded lands are proposed. In the summer and autumn of 2023, field visits were made to the territory of the Petrovsko-Anastasievskaya, Chernoerkovskaya, Azov and Temryuk irrigation systems in order to visually inspect them and take samples of water and soil for subsequent laboratory chemical analysis. Field visits were carried out during the beginning of the growing season and during the formation of the final drainage and discharge runoff, in order to track the dynamics of changes in the quality indicators of irrigation, waste water and soil. As a result of the conducted research, it was found that the quality of irrigation waters in the studied irrigation systems does not comply with irrigation standards. Chemical analysis of the soil from rice checks showed an excess of maximum permissible concentration (MPC) values of Cl-, SO42-, Na+ H NH4+ ions in the studied irrigation systems. Such results are facilitated by the spread of secondary salinization, since the Kuban River Delta is a modern accumulation of salts from the entire river basin. Soil salinization has a negative impact on agricultural production. Thus, with the help of timely monitoring of saline lands, it is possible to prevent degradation processes using effective melioration and reclamation methods.
7. T. D. PHUNG* [Climate change impacts on rice cultivation paddies in the Plain of Reeds, Vietnam]. Research on Crops 25 (2): 247-252 (2024). Faculty of Social Sciences Teacher Education Dong Thap University, Vietnam *(e-mail: ptduong@dthu.edu.vn)
ABSTRACT
Severe alterations in rainfall patterns have led to a shortage of irrigation water in rice paddies, resulting in income decline and spontaneous migration to urban centers. Recognizing the crucial significance of irrigation water for rice cultivation in the Plain of Reeds (PORs), this study aims to assess the impacts of rainfall characteristics alteration on rice yield in the concern of climate variation. The study focuses on variations in rainfall characteristics and their changing trends across the PORs. Non-parametric statistical approaches such as Mann-Kendall and Sen’s slope estimator and Standardized Precipitation Index (SPI) are employed for data analysis. The study utilizes daily rainfall data spanning 38 years (1985-2022) from the National Center for Hydrometeorological Forecasting (NCHF). The results demonstrate significant changes in rainfall characteristics such as rainfall in rainy season (RRS), date of the rainy season onset (DRSO) and date of the rainy season cessation (DRSC). Rice productivity exhibits substantial changes, with increases during La-Nina years and significant decreases during strong El-Niño events across the study area. The findings provide valuable insights for discussing and formulating policies on adaptive agricultural production methods in response to changing climate conditions, ensuring sustainable crop production in the region.
8. HAYDER ABID Al-RAZZAQ BAQIR AND NAJAT HUSSEIN ZEBOON* [Response of yield and its components of two wheat varieties to foliar spraying with stearic acid]. Research on Crops 25 (2): 253-257 (2024). College of Agriculture Engineering Science University of Baghdad, Baghdad, Iraq *(e-mail: najat.Zeboon@coagri.uobaghdad.edu.iq)
ABSTRACT
As a result of the excessive use of mineral fertilizers, it has led to an increase in the accumulation of pollutants in the soil and an imbalance in the elements present in it , leading to a decrease in crop productivity and quality, in addition to serious health problems for humans and animals, Therefore, attention in recent research has focused on the use of safe and environmentally friendly materials, including stearic acid, Therefore, a field experiment was conducted at Experiments Station affiliated to the Department of field crops, College of Agricultural Engineering Sciences, University of Baghdad during the winter season of 2022-2023, aiming to study the effect of foliar spraying with stearic acid on some traits of yield and its components of wheat. Randomized complete block design within split-plot arrangement with three replications was used. The study included two factors, the first (the main plots) represented two varieties of wheat (Buhooth 22 and Adina), while the second factor in the sub-plot represented spraying with stearic acid at three concentrations of 100, 200, and 300 mg/L, in addition to the control treatment (without spraying). The experiment results showed the superiority of the variety Buhooth 22 to Adina in most yield traits, as the highest average grain yield was recorded at 5.38 t/ha. Regarding the concentrations of the sprayed stearic acid, the results showed the superiority of the concentration 300 mg/L in number of spikes, weight of 1000 grain, grain yield, and harvest index. The concentration 300 mg/L didn’t differ significantly with the concentration mg/L in most traits, especially the total grain yield, which amounted to 5.88 t/ha. We conclude that Buhooth 22 cultivar and stearic acid with 200 mg/L concentration recorded the best results.
9. Naseer Faraj Shachai*, Ahmed Ali Hussein and Basheer Abdala Abraheem [Investigating the influence of growth inhibitors on the growth and yield of oat (Avena sativa)]. Research on Crops 25 (2): 258-262 (2024). 1Department of Field Crops Sciences College of Agricultural Engineering Sciences, University of Baghdad, Baghdad, Iraq. *(naser.faraj@coagri.uobaghdad.edu.iq)
ABSTRACT
Food security is a major challenge faced by countries around the world due to the large increases in population numbers, climate change, and the problems it causes in agricultural production, such as droughts, floods, and hurricanes. Most oat varieties are characterized by their long stems, and this makes them effective Sink for the deposition of dry matter that can be directed to the grain in the case of the use of growth inhibitors (such as Cycocel and ethylene) that suppress the longitudinal growth of the stems and increase its diameter, as well as increase the number of effective branches, reduces the risk of lodging, thus increasing the grain yield. This experiment was conducted in the fields of the College of Agricultural Engineering Sciences, University of Baghdad, during the winter season of 2020-2021, to assess the effects of growth inhibitors Cycocel )CCC( and calcium carbide CaC2 (which generates ethylene), used three replications of a randomized complete block design (RCBD), Eight treatments were tested, including spraying CCC at concentrations of 200, 400, and 600 mg/L and ground application of CaC2 at 2 g/plant individually and in combination. The findings revealed that all treatments led to an increase in grain yield and a decrease in plant height compared to the control treatment. Notably, the C600 + CaC2 treatment exhibited significant superiority over other treatments in grain yield (5.52 t/ha), total dry matter (20.14 t/ha), and Harvest Index (25.21). These results suggest that growth inhibitors can effectively modulate the source-sink relationship, thereby enhancing grain yield.
10. FATIMA E. ALDAINY AND BASHEER A. ABRAHEEM* [Assessment of maize leaf indicators under water reduction levels: Impact of polymer, charcoal, and antiperspirant treatments]. Research on Crops 25 (2): 263-268 (2024). Department of Field Crops Sciences College of Agricultural Engineering Sciences, University of Baghdad, Baghdad, Iraq. *(e-mail: Basher.abd@coagri.uobaghdad.edu.iq)
ABSTRACT
Water scarcity, exacerbated by climate change and international conflicts, poses significant challenges to maize production. Research has shown that interventions like plant charcoal, superabsorbent polymers, and anti-transpiration agents can mitigate water stress effects, enhancing maize growth indicators. Therefore, the experiment was conducted in the fields of the Department of Field Crops, College of Agricultural Engineering Sciences, University of Baghdad, in the spring season of 2022. The aim of the experiment was to increase the growth indicators of maize leaves exposed to water reduction levels using polymer, charcoal, and antiperspirant. The experiment was designed as a randomized complete block design (RCBD) in a split-plot arrangement with three replicates. The main plots were occupied by water reduction levels (0, 25 and 50%), while the subplots were occupied by the additives: sodium acrylate, biochar, antiperspirant, charcoal + antiperspirant, acrylate + antiperspirant, acrylate + charcoal + antiperspirant, and control. The charcoal treatment was able to join the binary and ternary treatments to give a significant increase over the other treatments in the number of leaves. In the weight of leaves, the acrylate + antiperspirant treatment was behind them, and they remained significantly superior. There was no significant difference observed among treatments in leaf area. However, the antiperspirant treatment exhibited the lowest percentage of leaf water loss, significantly differing from all other treatments. Additionally, the antiperspirant treatment consistently demonstrated the highest relative water content across all treatments in which it was applied, a trend similar to charcoal treatments. As for the interaction between the two factors of the study, it appeared that there was no significant difference in the charcoal + antiperspirant treatment at the levels of 0 and 25%, but the decrease became significant at the level of 50%.
11. MEHRNOUSH AMINISARTESHNIZI* [Analysing Pandoraea associated with Brassica oleracea using 16S rDNA from Limpopo Province, South Africa]. Research on Crops 25 (2): 269-272 (2024). Aquaculture Research Unit, School of Agricultural and Environmental Sciences, University of Limpopo, Private Bag X1106, Sovenga, 0727, South Africa *(e-mail: mehrnoush.aminisarteshnizi@ul.ac.za)
ABSTRACT
The genus Pandoraea comprises gram-negative, motile, non-spore-forming, rod-shaped, oxidase-positive, and obligate aerobes bacteria with a single polar flagellum. Several species belonging to this genus have been identified as potentially risky pathogenic bacteria, which can adversely impact the yield of white cabbage plants. A study was conducted at the University of Limpopo in 2023 to isolate and identify the Pandoraea bacterium from a white cabbage field and a free-living nematode, Acrobeles complexus, in South Africa. The molecular study used the 16S rDNA marker to identify the bacterium associated with nematode and white cabbage fields from South Africa’s soils. The DNA was extracted using the Chelex method, and the bacterium was identified as Pandoraea. Specific primers were used to amplify the 16S rDNA to identify the nematode. The Nblast analysis showed that South African Pandoraea has a 99% similarity with a population from India (AB510957). Phylogenetic analysis using maximum likelihood placed this species with those molecularly identified as Pandoraea in the same clade with highly supported (100) bootstrap values. In conclusion, this study has demonstrated that the 16S rDNA marker can be effectively used to identify Pandoraea species. However, the use of additional DNA markers is recommended to achieve a better understanding of Pandoraea’s phylogeny.
12. T. D. PHUNG* [Assessing the impact of unsustainable exploitation and climate change on soil properties alterations in the mountainous regions, Vietnam]. Research on Crops 25 (2): 273-279 (2024). Faculty of Social Sciences Teacher Education Dong Thap University, Vietnam *(e-mail: ptduong@dthu.edu.vn)
ABSTRACT
This study aims to assess the impacts of land use change (LUC) on soil properties and soil organic carbon content (SOCC) in the mountainous regions of Nghe An province, Vietnam. Soil samples were surveyed from forest plant area (FPA), annual plant area (APA), crop plant area (CPA), and bare hill area (BHA) at depths ranging from 0-50 cm during the period 2021-2023. The findings indicated that the conversion from FPA to BHA resulted in a significant decline in SOCC. In comparison to the topsoil layer, reductions of approximately 18.6-22.1% for FPA, 26.5-36.0% for CPA and APA, and up to 37.5% for BHA were observed in the soil profiles. These results underscore the sensitivity of SOCC to LUC across the study area. Moreover, the study contributes to our understanding of the implications of LUC on soil health and offers valuable insights for effective land management and conservation strategies. The conversion of FPA into various types of land use (TLU) has a detrimental impact on soil properties, highlighting the urgent necessity for sustainable land use practices.
13. T. N. LE, D. D. NGUYEN* AND D. T. NGUYEN [Land cover change assessment in Thai Nguyen Province, Vietnam using GIS and remote sensing techniques]. Research on Crops 25 (2): 280-285 (2024). Thai Nguyen University of Education, Vietnam *(e-mail: ndangdo@hueuni.edu.vn)
ABSTRACT
The expansion of agricultural production and urbanization has led to the depletion of the global forest ecosystem, resulting in land cover changes (LCCs) that pose threats to the land environment. Therefore, it is imperative to identify these LCCs as an essential step toward resolution and mitigation. This study aims to evaluate temporal LCCs in Thai Nguyen province by utilizing GIS and remote sensing techniques (RST) to analyze high-resolution satellite imagery spanning from 2001 to 2023. LCCs were identified using semi-automatic classification plugin (SCP) techniques with Landsat-8 and Sentinel-2 images in ERVI software. The accuracy of the LCC maps was validated through post-classification comparisons, yielding high precision rates ranging from 87% to 96%. The results indicate a significant reduction in forest cover area, declining by 1018 ha from 226,18 ha in 2001 to 207,22 ha in 2023. This decline primarily occurred in urban areas, highlighting the intensification of urbanization processes. Cultivated and bare land experienced a minor decrease and a substantial decrease from 18,631 ha and 105,000 ha to 16,578 ha and 86,82 ha between 2001 and 2010, followed by a slight increase and a significant increase to 5,069 ha and 24,487 ha (1.4% and 6.9%) during the 2010-2023 period. These findings underscore the escalating risk of diminishing forest cover in the study area.
14. CUCU SUHERMAN*, JAJANG SUPRIATNA, ANNE NURAINI AND SYARIFUL MUBAROK [Optimizing oil palm farming: Soil quality, fertilization and agro-environmental performance]. Research on Crops 25 (2): 286-291 (2024). Department of Agronomy Faculty of Agriculture Padjadjaran University, Bandung 45363, Indonesia *(e-mail: cucu.suherman@unpad.ac.id)
ABSTRACT
The essential role of fertilization in the management of oil palm plantations cannot be overstated, with the understanding that effective strategies must be fine-tuned to accommodate the diversity of soil types present. The nuanced response of oil palm to fertilization under different soil conditions underscores the critical nature of this research. This study investigates the relationship between oil palm farming practices and agro-environmental performance of plantations. This research aims to understand the complex mechanisms influencing plantation productivity. Five agronomic field experiments were carried out on various soil types (Podzol, Inceptisol, Peat) during 2022. These experiments involved various types of soil and used different plant materials in a total land area of 33 hectares. The results of the peat soil trials revealed a positive effect of RP fertilizer on leaf phosphorus (P) content and a visible gradient in potassium (K) content with different doses of KCl. Average plantation yields peaked in 2022, showing the best yields ever recorded. On the contrary, experiments in podzolic soils showed that oil palm responded better to organic fertilizers than to mineral fertilizers in podzolic soils. The inceptisol soil revealed a significant increase in leaf potassium (K) content with KCl dose, confirming the positive effect of fresh oil palm empty fruit bunches (EFB) on potassium levels. In particular, EFB acts as a good K fertilizer, positively influencing the K content but negatively affecting the calcium content (Ca) due to K/Ca antagonism. These findings emphasize the need for diversified agricultural strategies to optimize oil palm cultivation, increase productivity, and reduce dependence on external input.
15. GAVIN GELDENHUYS* [Evaluating the efficiency of Chelex 100 for DNA extraction in orange (Citrus sinensis)]. Research on Crops 25 (2): 292-295 (2024). Aquaculture Research Unit, School of Agricultural and Environmental Sciences, University of Limpopo (Turfloop Campus) Private Bag X1106, Sovenga, 0727, South Africa *(e-mail: gavin.geldenhuys@ul.ac.za)
ABSTRACT
Plant research has recently concentrated on the molecular level, which requires reliable, inexpensive, and fast protocols for extracting DNA. Many researchers have identified Chelex-based DNA extraction methods as having the potential to reduce costs. However, Chelex can also prevent DNA degradation by chelating metal ions. Citrus is one of the top three crops grown globally, with oranges being a well-known species. Therefore, study on the molecular of C. sinensis is essential. This study was conducted in 2022 at the genetic lab of the University of Limpopo- to compare two different extraction methods for DNA from C. sinensis. The DNA from the C. sinensis leaves was extracted using Chelex “method 1” (overnight incubation at 56°C) and “method 2” (Ten-minute incubation at 95°C). A spectrophotometer was employed to measure the extracted DNA’s qualitative and quantitative parameters accurately. Furthermore, all samples were subjected to PCR reactions with primers for 28S. The results indicated that “method 2” (1.59-1.84) proved to be the most effective method to obtain high-quality extracted DNA. Additionally, the quantitative and qualitative tests for PCR reaction demonstrated that “method 2” produced better results. In conclusion, although both methods yielded favourable outcomes, “method 2” was ultimately the more successful approach.
16. K. P. MALATJI, P. W. MASHELA* AND K. M. POFU [Response of selected nutrient elements in leaf tissues of sweet potato cv. ‘Bophelo’ to Nemafric-BL phytonematicide]. Research on Crops 25 (2): 296-301 (2024). University of Limpopo, Department of Plant Production, Soil Science and Agricultural Engineering, Green Biotechnologies Research Centre of Excellence Private Bag X1106, Sovenga, 0727, Republic of South Africa *(e-mail: phatu.mashela@ul.ac.za)
ABSTRACT
Nemafric-BL phytonematicide is a potent plant-based nematicide which consistently suppress nematode population densities of root-knot (Meloidogyne species) nematodes on various crops, but with limited information on its effects on foliar nutrient elements in sweet potato. The objective of this study, therefore, was to investigate the effects of Nemafric-BL phytonematicide on accumulation of nutrient elements in leaf tissues of sweet potato cv. ‘Bophelo’ under greenhouse conditions in Limpopo Province, South Africa, during autumn (February-April) in 2021 and validated in 2022. The product was applied weekly at geometric concentrations, with mature leaves collected and prepared for analysis of nutrient elements at eight weeks. Seasonal interactions were not significant and therefore data were pooled (n = 70) and then subjected to the Curve-fitting Allelochemical Response Dose (CARD) algorithm computer model. Iron (R2 = 0.86), K (0.91) and Na (0.82) versus Nemafric-BL phytonematicide each exhibited negative quadratic relations, whereas Zn (0.83) versus the product exhibited positive quadratic relations. In all test elements, the CARD-generated biological indices illustrated that the accumulation of elements was highly sensitive to the concentration of Nemafric-BL phytonematicide. In conclusion, in sweet potato production, the application of Nemafric-BL phytonematicide can inhibit (Fe, K) and stimulate (Zn) the accumulation of certain elements in leaf tissues of sweet potato cv. ‘Bophelo’.
17. RYAN WIDIANTO* AND DENNY KURNIADIE [Chemical desiccation of potato haulms to increase skin hardness and potato yield]. Research on Crops 25 (2): 302-307 (2024). Department of Agronomy, Faculty of Agriculture Padjadjaran University, Jatinangor, Sumedang, 45363, Indonesia *(e-mail: ryanwidianto21@hotmail.com)
ABSTRACT
Desiccation of potato crops using herbicides is one of the methods widely used by farmers. Desiccation affects several key aspects such as tuber yield and potato skin hardness. This study aimed to investigate the effects of desiccation on potato (Solanum tuberosum L.) on skin hardness and yield. Experimental methods were used by varying the level of desiccation on different herbicide groups. Ammonium glufosinate, glyphosate, paraquat and saflufenacil herbicides were used in this study which were then compared with manual trimming and no desiccation treatment. The results showed that all herbicides reached a percentage of desiccation above 95% on the 15 days after application. All herbicide treatments other than glyphosate showed the same potato skin hardness as the manual trimming treatment and were harder than potato tubers without desiccation treatment. Desiccation using ammonium glufosinate herbicide at 375 g a.i./ha had the highest potato tuber yield compared to other herbicide applications.
18. Gavin Geldenhuys* [Investigation on the population dynamics of Helicotylenchus pseudorobustus and its relationship with soil factors in tomato fields]. Research on Crops 25 (2): 308-311 (2024). Aquaculture Research Unit, School of Agricultural and Environmental Sciences, University of Limpopo, Private Bag X1106, Sovenga, 0727, South Africa *(e-mail: gavin.geldenhuys@ul.ac.za)
ABSTRACT
Tomato (Solanum lycopersicum L.) is one of the premier vegetables in the world and is widely cultivated globally. As it is a relatively short-duration crop with a high yield, it is economically attractive, and the area under cultivation is increasing. Plant-parasitic nematodes are some of the most important plant pathogens in tomato farms. Helicotylenchus pseudorobustus is one of the most important plant-parasitic nematodes in tomato fields. Therefore, understanding the population dynamics of H. pseudorobustus on the tomato field assists the farmer in managing them and having better yields. In this study, the soil was sampled in 2022. Identification and determination of nematodes were made in the Aquaculture Research Unit, University of Limpopo. The properties of soils infected with this nematode, including pH and EC, were investigated during the investigation of this nematode in the Dalmatia region. The population of H. pseudorobustus was counted in 100 grams of soil in each season, and soil characteristics were also analyzed at the same time. The results in different seasons of the year showed that the range of pH changes during the years of investigation was between 7.5 and 7.7, and the range of EC changes was between 1.3 and 2.0 dS/m. A comparison of EC and pH changes with population changes showed that the population increased approximately in the months when soil salinity decreased. In addition, as the pH increases, the population of H. pseudorobustus also increases. However, no significant relationship was found between the values of pH, EC, and changes in the population of H. pseudorobustus nematode throughout the year.
19. GAVIN GELDENHUYS* [Identification of molecular characters of tomato seedlings (Solanum lycopersicum) from Limpopo Province, South Africa, using 28S rDNA]. Research on Crops 25 (2): 312-315 (2024). 1Aquaculture Research Unit, School of Agricultural and Environmental Sciences, University of Limpopo (Turfloop Campus), Private Bag X1106 Sovenga, 0727, South Africa *(e-mail: gavin.geldenhuys@ul.ac.za)
ABSTRACT
Farming with tomatoes (Solanum lycopersicum) in South Africa can be a highly profitable operation, provided the farmer starts the crop with the right variety of quality seedlings, suited for the specific growth area. Therefore, it is necessary to study tomato seedlings on the molecular level. This study was conducted to isolate and identify S. lycopersicum in Limpopo Province, South Africa. Therefore, this molecular study was conducted in 2022 at Limpopo University. To identify S. lycopersicum 28S rDNA marker was used. The DNA was extracted using the Chelex method. The tomato was identified as S. lycopersicum. The Nblast analysis showed South African S. lycopersicum has a 99.8% similarity with a population from Germany (OU640345) and a 99.7% similarity with a population from Sweden (OK073662). Phylogenetic analysis using maximum likelihood placed this species with those molecularly identified as S. lycopersicum in the same clade with highly supported (83) bootstrap values. In conclusion, this species is identified using 28S rDNA properly. However, other DNA markers are recommended to understand Solanum spp. phylogeny better.
20. Bushra Solanki* and Mohd Saghir Khan [Unveiling the efficacy of a bacterial antagonist in the management of tomato wilt disease caused by Ralstonia solanacearum]. Research on Crops 25 (2): 316-323 (2024). Department of Agricultural Microbiology, Faculty of Agricultural Sciences Aligarh Muslim University, Aligarh-202 002 (U. P.), India *(e-mail: bushrasolanki2395@gmail.com)
ABSTRACT
The long-term application of agrochemicals, including pesticides, in intensive agricultural practices to protect crops from biotic stresses results in the emergence of resistance among phytopathogens and the ineffectiveness of chemical applications. The microbiological strategies, in contrast, minimize the reliance on chemicals and, hence, reduce environmental and human health risks. Bacterial wilt of tomato induced by Ralstonia solanacearum is one of the most destructive diseases worldwide that requires urgent attention to develop a safer and more efficient method to control the phytopathogen. The present work was conducted in the year 2022-2023. In this study, the bacterial wilt was managed by an antagonist bacterium, Pseudomonas fluorescens, exhibiting variable morphological, biochemical, and plant growth-promoting activities. The P. fluorescens inhibited the growth of R. solanacearum in plate assay at different time intervals (0-48 h). The SEM image of R. solanacearum cells cultured with P. fluorescens revealed pores, distortion, and fragmented cell envelope, while the untreated bacterial cells were uniform and smooth. Tomato plants infected with R. solanacearum showed 89% disease incidence compared to uninfected but PGPR-inoculated tomato plants. Application of P. fluorescens reduced disease incidence by 63% compared to R. solanacearum infested plants. Furthermore, plant length enhanced by 21 and 26% significantly following bacterial inoculation after three and four weeks of growth. Conclusively, this study emphasizes the effectiveness of using PGPR as a potent strategy for managing wilt disease in vegetable crops, especially tomato.
21. Gavin Geldenhuys* [Relationship between soil factors with Helicotylenchus pseudorobustus isolated from tomato fields in Limpopo Province, South Africa]. Research on Crops 25 (2): 324-327 (2024). Aquaculture Research Unit, School of Agricultural and Environmental Sciences, University of Limpopo, Private Bag X1106, Sovenga, 0727, South Africa *(e-mail: gavin.geldenhuys@ul.ac.za)
ABSTRACT
Helicotylenchus pseudorobustus is one of the tomato fields’ most important plant-parasitic nematodes. In this study, the soil was sampled in 2023. The identification and determination of nematodes was made in the Aquaculture Research Unit at the University of Limpopo. During the investigation of this nematode in the Tzaneen region, the properties of soils infected with this nematode, including pH and EC, were investigated. The population of H. pseudorobustus was counted in 100 grams of soil in each season, and soil characteristics were also analysed at the same time. The results in different seasons of the year showed that the range of pH changes during the year of investigation was between 5.2 and 6.6, and the range of EC changes was between 2.9 and 4.3 mS. A comparison of EC and pH changes with population changes showed that the population increased approximately in the months when soil salinity decreased. In addition, soil structure (71.9% sand, 8.0% silt, and 20.1% clay) didn’t influence the H. pseudorobustus population. However, the results showed no significant relationship between soil factors and the population dynamic of H. pseudorobustus nematode throughout the year.
22. SAGAR MAITRA, MASINA SAIRAM*, D. T. SANTOSH, DINKAR JAGANNATH GAIKWAD AND UPASANA SAHOO [Growth, productivity and quality of colored capsicum (Capsicum annuum L.) as influenced by hybrids and plant growth regulators under controlled environment conditions]. Research on Crops 25 (2): 328-335 (2024). Department of Agronomy and Agroforestry, Centurion University of Technology and Management, Paralakhemundi-761 211, Odisha, India *(e mail: sairam.masina@cutm.ac.in)
ABSTRACT
In developing countries like India, rapid urbanisation was under way and the diet habits of the people have been changing day to day. Under this transformation, a section of the population is focused on nutritional security where vegetables play a major role in daily diet. Among different vegetables coloured bell pepper which is commonly known as capsicum, has importance due to its nutritional quality and market demand. The quality and productivity of coloured capsicum can be improved by choosing the best performing hybrids and exogenous application of plant growth regulators. Considering the above, the present study was conducted from November to April of 2020-21 and 2021-22 at the Protected Cultivation Unit of Centurion University of Technology and Management, Paralakhemundi, Odisha under controlled environment conditions. The experiment was laid out in factorial randomized block design consisting of two hybrids, namely, Orobelle (yellow colored) and Bomby (red colored); and eight treatments of growth regulators which were GA3 @ 25 ppm, GA3 @ 50 ppm, GA3 @ 75 ppm, GA3 @ 100 ppm, NAA @ 20 ppm, NAA @ 40 ppm, NAA @ 60 ppm and NAA @ 80 ppm. A total of 16 treatment combinations were worked out in the experiment which were replicated thrice. The results of the experiment revealed that there was no significant variation among the hybrids cultivated with respect to yield attributes, yield, quality parameters and growth attributes excluding plant height and number of leaves per plant at 60 DAS and 90 DAS. However, there was a significant impact of plant growth regulators on growth attributes, yield attributes, yield and quality parameters. The application of NAA @ 80 ppm resulted in early flowering (43.8 days after planting). Moreover, the maximum number of flowers per plant (32.5 flowers/plant), flower to fruit ratio (52.9), fruits per plant (19.5) and weight of the fruit (133.6 g) recorded in GA3 @ 100 ppm application. There was a significant interaction effect among treatment combinations in fruit yield where the highest value was recorded in Bomby hybrid with GA3 @ 100 PPM application. From the study it may be concluded that cultivation of both the hybrids can be considered as per the fruit colour and market demand along with the application of GA3 @ 100 ppm under controlled environment conditions.
23. MAROPENG CHOSHI AND YVONNE MAILA* [Influence of growth stages on the nutritional value of Momordica balsamina leaf powder]. Research on Crops 25 (2): 336-342 (2024). University of Limpopo, Department of Plant Production, Soil Science and Agricultural Engineering, Private Bag x1106, Sovenga, 0727, Polokwane, South Africa *(e-mail: yvonne.maila@ul.ac.za)
ABSTRACT
The nutritive mineral element concentrations of most African leafy vegetables (ALVs) are influenced by the plant’s growth stages. Momordica balsamina is an ALV in the Cucurbitaceae family, rich with nutraceutical and pharmaceutical properties, available in the plant at different growth stages. A greenhouse study was conducted to determine the responses of the nutritional value of M. balsamina leafy vegetable harvested at different growth stages. Six growth stages, namely, vegetative (reference), bud development, flower initiation, fruit set, fruit development and physiological maturity, served as treatments, with 10 replicates and arranged in RCBD. Treatments had highly significant (P 0.01) effect on the tested nutritional quality, namely, potassium (K), calcium (Ca), magnesium (Mg), zinc (Zn), iron (Fe) and phosphorus (P). Relative to the reference, K was the highest (1206 mg/L) at flower initiation stage, whereas the highest Ca (127.70 mg/L) and Zn (2.21 mg/L) concentrations occurred at the fruit development stage. At the physiological maturity stage, the highest Mg (25.19 mg/L), P (16.54 mg/L) and Fe (5.49 mg/L) concentrations, were recorded. Noticeably, during early growth stages, P, Fe and Zn were negatively reduced, when compared to K, Ca and Mg, which were increasing at every growth stages. In conclusion, the greatest accumulation of the tested mineral elements was mainly observed as from when the leafy vegetable started setting fruit until physiological maturity stage.
24. MOSES TIMANA*, ZAKHELENI DUBE, NCOBILE NKUNA, MMAGADIMA SEBATI, THOBILE MKHWANAZI AND RIVONINGO UBISI [Sphenoptera sp. (Buprestidae: Coleoptera) threatening wild cancer bush (Sutherlandia frutescens) population]. Research on Crops 25 (2): 343-349 (2024). University of Mpumalanga Private Bag X11283, Mbombela, 1200, South Africa *(e-mail: 201626276@ump.ac.za)
ABSTRACT
Cancer bush (Sutherlandia frutescens) is a medicinal plant indigenous to Southern Africa, important in the treatment of diverse human diseases and ailments. The rampant harvesting in the wild has threatened many indigenous medicinal plants. To safeguard this national treasure, cultivation has been recommended. Recently, substantial insect damage to the wild population of cancer bush in the Limpopo province has been observed. Currently, there are no reports of insect pests associated with cancer bush, hence the objective of this study was to use morphological and molecular tools in the identification of insect pest associated with extensive damage to wild cancer bush populations in Makgophong and Tubatse, Limpopo Province, South Africa from March to June 2023. Plants were cut longitudinally to expose insects inside the stem, and a microscope at 40X magnification, was used to examine the morphological characteristics of insects found. Insect species found were further confirmed using mitochondrial cytochrome c oxidase subunit 1 gene (COI). All life stages of the beetle except the egg stage were observed in the plant, and the morphological and molecular examination of these specimens revealed that the adults and larvae corresponded with the descriptions of Sphenoptera species. This is the first positive confirmation of Sphenoptera species associated with cancer bush and urgent development of management strategies is needed if this plant population (species) is to be conserved.
25. MEHRNOUSH AMINISARTESHNIZI* [Phylogenetic position of Aceria sp. (Trombidiformes: Eriophyidae) based on 28S rDNA partial sequences Limpopo Province, South Africa]. Research on Crops 25 (2): 350-352 (2024). Aquaculture Research Unit, School of Agricultural and Environmental Sciences, University of Limpopo, Private Bag X1106, Sovenga, 0727, South Africa *(e-mail: mehrnoush.aminisarteshnizi@ul.ac.za)
ABSTRACT
Aceria (Trombidiformes: Eriophyidae) is the largest known genus among the Eriophyoidea and is associated with economically important crops as pest species are distributed worldwide. Therefore, correctly identifying them for their control and management is necessary. This study was conducted to isolate and identify Aceria sp. in Limpopo Province, South Africa. Therefore, this molecular study was conducted in 2023 at Limpopo University. To identify Aceria sp., 28S rDNA marker used. The DNA was extracted using the Chelex method. The Aceria was identified as Aceria sp. The Nblast analysis showed South African Aceria sp. has 92% similarity with a population from Russia (OP419491). Phylogenetic analysis using maximum likelihood placed this species with those molecularly identified as Aceria sp. in the same clade with highly supported (96) bootstrap values. In conclusion, this species is identified using 28S rDNA properly. However, other DNA markers are recommended to better understand Aceria sp. phylogeny.
26. MEHRNOUSH AMINISARTESHNIZI* [Phylogenetic position of Discolaimium (Nematoda: Dorylaimida) from South Africa using 28S rDNA]. Research on Crops 25 (2): 353-355 (2024). Aquaculture Research Unit, School of Agricultural and Environmental Sciences, University of Limpopo, Private Bag X1106, Sovenga, 0727, South Africa *(e-mail: mehrnoush.aminisarteshnizi@ul.ac.za)
ABSTRACT
Dorylaim nematodes inhabit soil and are predatory, primarily feeding on other nematodes. This predatory behaviour positions them as a potential natural solution to combat plant-parasitic nematodes. By preying on their fellow nematodes, they contribute significantly to ecological diversity. Therefore, this molecular study was conducted in 2022 at the University of Limpopo to identify the soil nematodes from South Africa using a 28S rDNA marker. The recovered nematode was extracted using the tray method. The Chelex method was used to extract DNA, and the nematode was identified as Discolaimium. Afterward, 28S rDNA was amplified using specific primers to identify the nematode. The Nblast analysis based on the small subunit ribosomal DNA showed that South African Discolaimium has a 97% similarity (MG921263) with the Chinese population of Discolaimium. Phylogenetic analysis using maximum likelihood placed this species with those molecularly identified as Discolaimium in the same clade with highly supported (100) bootstrap values. In conclusion, this species was properly identified using 28S rDNA. However, other DNA markers are recommended to understand the Discolaimium phylogeny better.
27. Agus Susanto*, Wahyu Daradjat Natawigena, Yayan Sumekar and Arief Nasrullah Hidayath [Toxicity of several insecticides against fruit flies Bactrocera dorsalis (Hendel) and Bactrocera carambolae (Drew & Hancock) (Diptera: Tephritidae) in the laboratory]. Research on Crops 25 (2): 356-361 (2024). Faculty of Agriculture, Universitas Padjadjaran Jalan Raya Bandung-Sumedang Km 21, Jatinangor, Indonesia *(e-mail: asusanto@unpad.ac.id)
ABSTRACT
Bactrocera dorsalis and Bactrocera carambolae are major pests of various commodities that could cause significant losses, if not controlled. Insecticide usage is a common control carried out by farmers. The test was conducted to determine the toxicity level of several types of insecticides on the mortality of two different fruit fly species. The fruit fly population used in the study came from the collection owned by Center for Forecasting Plant Pest Organisms (BBPOPT), Karawang. The research method used was an experimental method with a Randomized Block Design. The test was carried out using the dry film method. The concentration ranges used were 0.02-1 ml/L fipronil insecticide, 0.01-0.6 ml/L ethion insecticide, 0.02-0.6 ml/L deltamethrin insecticide, and 0.02-0.8 ml/L lambda-cyhalothrin insecticide. The control treatment used was acetone alone. Each treatment was replicated thrice. Mortality was observed at 1, 3, 24, and 48 hours after treatment. Cumulative mortality at 48 hours after treatment was analyzed using probit to determine the LC50 and LC95 values at 48 hours. The results showed that the insecticide deltamethrin was the most toxic insecticide to B. carambolae with an LC50 value of 0.025 ml/L and an LC95 of 0.646 ml/L. Ethion was the most toxic insecticide for B. dorsalis with LC50 values of 0.046 ml/L and LC95 of 0.746 ml/L. The LC50 values of all insecticide treatments for two different species were below the recommended concentrations.
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