No abstract

Sesame is sensitive to waterlogging, and its growth is devastatingly impacted under excess moisture conditions. Thus, waterlogging tolerance is crucial to alleviate yield constraints, particularly under expected climate change. In this study, 119 diverse sesame genotypes were screened for their tolerance to 12, 24, 48, and 72 h of waterlogging relative to non-waterlogged conditions. All plants died under 72 h of waterlogging, while 13.45%, 31.93%, and 45.38% of genotypes survived at 48, 24, and 12 h, respectively. Based on the seedling parameters and waterlogging tolerance coefficients, genotypes BD-7008 and BD-6985 exhibited the highest tolerance to waterlogging, while BD-6996 and JP-01811 were the most sensitive ones. The responses of these four genotypes to waterlogged conditions were assessed at different plant growth stages—30, 40, and 50 days after sowing (DAS)—versus normal conditions. Waterlogging, particularly when it occurred within 30 DAS, destructively affected the physiological and morphological characteristics, which was reflected in the growth and yield attributes. Genotype BD-7008, followed by BD-6985, exhibited the highest chlorophyll and proline contents as well as enzymatic antioxidant activities, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). These biochemical and physiological adjustments ameliorated the adverse effects of waterlogging, resulting in higher yields for both genotypes. Conversely, JP-01811 presented the lowest chlorophyll and proline contents as well as enzymatic antioxidant activities, resulting in the poorest growth and seed yield.

Mycorrhiza has been known could increase plants’ nutrient uptake through promoting root zone which resulted in higher yield production. A glasshouse experiment was conducted to optimize the technology for arbuscular mycorrhiza biofertilizer production through hydroponic system with automatic watering system and nutrient solution modification. Sorghum bicolor was used as host plants, grown for six weeks on medium contained mixture of zeolite and rice husk charcoal with the addition of arbuscular mycorrhizal fungi inoculum. Different hydroponic techniques (Deep Flow and Ebb Flow) and phosphorus content in nutrient solutions (0, 20, 40, 80 ppm) were tested. Results showed that different types of hydroponic system and rates of P in nutrient solution gave significant differences in increasing mycorrhizal colonization in roots, number of mycorrhizal spores, P uptake and biomass of plants. The best hydroponic technique was Ebb Flow with P content 40 ppm which was 50% lower than the standard nutrient solution for hydroponic. These findings suggest that the production of mycorrhiza biofertilizer through optimization of nutrient solution and growing medium in hydroponic system was potential for future practice. This technology could be used for mass production of “clean” and good quality of mycorrhizal biofertilizer.

Personal protection equipment (PPE) is used by farmers when dealing with crop protection products. Owing to its relevance, this survey assessed the status of PPE use by the farmers. The survey focused on two districts (Jeshore and Rajshahi) of Bangladesh. Descriptive research design was used to achieve the survey objective including both quantitative and qualitative techniques. Findings revealed that the mean age of respondents was 39.5 years with an average annual income of BDT 194,540.0 (USD 2,434.8), having very poor training exposure, but expressed positive perception on PPE use. Upon exposure to any crop protection product, the farmers wash it off immediately, and mostly clean with soap and water within one hour of spray completion. Frequently experienced difficulty was skin burn, and whenever contamination or poisoning occurs local domestic first aid methods were adopted or contact was made to village quacks. Qualitative findings revealed similar information, however, in addition, farmers especially, youth were found to have adopted “traditional PPE,” which involves wearing of trousers, long sleeve shirts, polythene in place of hand gloves and cotton napkin to cover their faces. It was suggested that organized campaigns and effective information dissemination would encourage adequate and proper application of PPE. Use of PPE becomes inevitable for farmers’ safety with advancement in science and technology and its consequential effects. It is, therefore, obvious that the all stakeholders in agriculture and agri-allied industries take awareness creation and training on PPE use as part of their core agenda to avert hazard and ensure safety.

Emergent aquatic weeds present in the monocropped fresh water wetland area of Bangladesh create a hazard in land preparation by developing dense stands. A field experiment was conducted at the farmers' field of two villages namely Mahilara and Kashemabad under Gournadi Upazila of Barisal district, Bangladesh during October 2012 to evaluate the efficacy of Gramoxone 20SL (Paraquat) in controlling emergent aquatic weeds and to find out an appropriate dose of this herbicide. Three doses of Gramoxone 20SL at 1.96 l·ha −1 , 2.00 l·ha −1 and 2.04 l·ha −1 were tried with an untreated control. All treatments were laid out in a randomized complete block design and replicated thrice. There were 8 different emergent weed species infesting the field among which the most dominant weed species were Eichhornia crassipes, Pistia stratiotes, Enhydra fluctuans, Monochoria vaginalis, Echinochloa crus-galli. The results revealed that, weed control efficiency was significantly affected by different herbicidal treatments. The treatments, Gramoxone 20SL at 2.00 l·ha −1 and 2.04 l·ha −1 were controlled in all the emergent aquatic weeds more than 85% infesting both the sites. Application of non-selective herbicide Gramoxone 20SL at 2.00 l·ha −1 prior to land preparation was most effective to suppress weed dry masses in both the site resulting reduced land preparation cost up to 78.93% as compared to manual weed control.