Azarian Journal of Agriculture
Volume:8 Issue: 1, Feb 2021

The current study evaluated the effects of cadmium stress on the antioxidant responses of Vigna radiata L. Wilcziek. The treatments consisted of 0, 25, 50, 75, and 100 ppm of CdCl2 2H2O. Seeds were placed in plastic trays and watered with distilled water. After 24 hours, the seeds germinated, and then they were transferred to pots. We irrigated each pot with their desired treatment solution until the end of the growth phase. A sampling of mature leaves at the flowering time was done. The concentration of cadmium in soil and other tissues of the plant, the level of leaves soluble proteins, ascorbate peroxidase (APx) and peroxidase enzymes (POD), total antioxidant capacities (TAC), and concentration of hydrogen peroxide (H2O2 ) in the samples were measured and compared to control. The lowest level of soluble protein (73.75±6.8 mg L-1 ) was observed in the 50 mg Cd/L treatments. The maximum rate of H2O2 (1.82±0.06 μM g-1 frw) and APx (0.83±0.04 U gfrw-1 ) activity was measured in treatment of 25 mg Cd/L and the lowest was observed in the treatment of 100 mg Cd/L (1.16±0.08 μM g-1 frw and 0.19±0.02 U gfrw-1 , respectively). The highest and lowest level of POD was observed in the treatment of 75 mg Cd/L (1.93±0.03 U gfrw-1 ) and 100 mg Cd/L (0.12±0.02 U gfrw-1 ), respectively. The Mung bean plant has a resistance to cadmium stress even up to 100 ppm. This resistance appears to be due to the high total antioxidant capacity of the V. radiata. Hereupon, mung bean can provide a safe culture for cadmium-contaminated environments.

The study assesses the efficacy of biological and chemical treatments to control potato powdery scab at the farmer’s field of Dadeldhura district. The experiment was conducted in a randomized complete block design with 5 treatments and 4 replications. The treatments were Mancozeb, Boric acid, Trichoderma viride, Pseudomonas fluorescens and Non-Treated Control. Cardinal variety of potato was chosen as planting material. The effectiveness of different treatments against potato powdery scab disease was evaluated along with different growth and yield parameters. Significant influences of treatments on disease and yield parameters were observed. Among the treatments, Pseudomonas fluorescens treated tubers showed the least disease incidence (45%) and severity percentage (23.35%). Although, the disease incidence (52.5%) and severity percentage (28.70%) of Trichoderma viride treated plots were found higher but were statistically at par with pseudomonas treated plots while the highest disease incidence (92.5%) and severity percentage (42%) was observed under Non Treated control (NTC). Moreover, Marketable yield (mt ha-1 ) was observed highest from (34.62mt ha-1 ) Pseudomonas followed by Trichoderma viride (28.62mt ha-1 ) and the least yield (15.81mt ha-1 ) was obtained in boric acid) and Non Treated Control (16.76 mt ha-1 ). Similarly, higher returns (NRs. 1315910) and B:C ratio (4.79) were obtained in Pseudomonas fluorescens followed by Trichoderma viride (NRs. 1087795 and 3.97 respectively) and least in Boric acid (NRs.600945 and 2.21). From the results, it can be concluded that antagonistic such as Pseudomonas fluorescens and Trichoderma viride are effective and more economical for reducing potato powdery scab severity and increasing the marketable yield of potato tubers under Dadeldhura conditions.

The brown marmorated stink bug (BMSB) is an important invasive stink bug species which is native to Asia and spread to America causing serious losses to agricultural crops. Laboratory experiments were conducted to assess the preference of BMSB for three phenological growth stages (leaf, flower and pod) of two cowpea cultivars (Early Scarlet and Mississippi Silver). These two cowpea cultivars were selected based on a previous multiple choice and no choice experiments in which they were highly preferred by the BMSB compared to the other host plants which included soybean, corn, sunflower and princess tree leaves. To assess host plant selection by the BMSB, we used a four-arm olfactometer to determine plant volatile involvement in the observed preferences and in the decision making of the insects. The Noldus Observer XT video system was used to record the insect’s activities based on visual cues. Results from these experiments show that BMSBs were attracted to both the vegetative and reproductive structures of Mississippi Silver, an indication that this cowpea variety could be used as a trap crop, although it should be verified through field experiment.

A three-year (2012 - 2015) longer wet rice-wheat-jute crop rotation experiment was sampled from the Rajbari district of Bangladesh. The objective was to study the effects of strip tillage (ST), bed planting (BP), and zero tillage (ZT) relative to conventional tillage (CT) with increased residues (20 vs. 50%) of previous crops on the composition of soil weed seed pool. The weed abundance at 0-15 cm soil profile was quantified following “seedling germination method” at the green-house of Bangladesh Agricultural University during January - December 2016. The year-round count of germinated weeds revealed the fewest number of species, and the lowest density of broadleaf, grass, and sedge weeds were found in ST, followed by CT, BP, and ZT with 50% crop residues. The diversity of weed flora having some specific weeds was the least at ST but the ZT was the most diversified followed by BP and CT. The ST plus 50% residue decreased the weed composition. Still, they increased the relative proliferation of perennial weeds compared to CT. Weed composition in ST was even smaller than BP and ZT. The ST, BP, and ZT enriched the abundance of perennial weeds: Alternanthera sessilis, Leersia hexandra, Dentella repens, Jussia deccurence, Solanum torvum, Hedyotis corymbosa. On the other hand, annual weeds: Euphorbia parviflora, Cyperus iria, Monochoria hastata, Digitaria sanguinalis, Lindernia antipoda, L. hyssopifolia and Fimbristylis miliacea were dominated the weed seedbank at 0-15 cm soil profile after three years of cropping in Bangladesh.