Blast is a major rice disease that can affect rice plant during all growth stages, wherein causing drastic yield loss globally. Host-plant resistance has been the most practical and cost effective approach to control insect pests and diseases in crops. Therefore, eighty (80) rice genotypes were screened for resistance to the leaf blast and brown plant hopper at Hybrid Rice Evaluation Centre, Gudalur, The Nilgiris District, Tamil Nadu, India. The study site is known as blast and brown plant hopper (BPH) hot spot in India. The genotypes were evaluated according to the standard evaluation system for rice. The results revealed that nineteen (19) genotypes namely; CB08504, CB13506, CB14528, CB14681, PR114, ORJ1141, CR3868-225-1-2-2-5, MTU1156, NDR2111-13-1, PAU3835-12-1-1-2, MTU1157, HKR08-1, CT16658-5-2-3SR-2-1MMP, IR10A136, CB14149, CO(R) 49, Ciherang, IR11A294 and EC578527 showed resistant reaction and 27 genotypes were found to be moderately resistant to the leaf blast disease. None of the genotypes was immune to BPH reaction. Four (4) genotypes were resistant, and twenty-three (23) were moderately resistant. The genotypes viz., CR3868-225-1-2-2-5 and NDR 2111-13-1 which were resistant to leaf blast showed moderate resistance to BPH. Genotypes like HHZ 17-DT-6-Sal3-DT 1, BRR 0015, PAU 3842-60-5-1-3, Vanjinathan and EC 465120 were moderately resistant to both blast and BPH. These genotypes identified may be utilized as genetic sources for multiple resistant genes in rice improvement.

Pollen viability and germinability are indispensable criteria in plant breeding programmes. This research evaluated eleven M4 mutant lines of gamma irradiated sesame (Sesamum indicum) for some pollen parameters. Seeds were obtained from the Department of Plant Biology, Federal University of Technology, Minna and were raised to maturity alongside their respective checks in a randomized complete block design (RCBD). The field experiment was conducted at the experimental field of the Upper Niger River Basin Development Authority, Minna. Pollen viability and diameter were determined using standard procedure. The germinability test was done using three different sucrose concentrations (10 %, 20 % and 30 %) with 1 % nutrient agar solution. The results revealed that all the M4 mutant lines had adequate pollen viabilities (over 80%) with ML-10 having the highest (97.56 %) viability followed by ML-7 (95.61 %), ML-8 (95.01 %) and Check-2 (95.60 %). The highest pollen germinability was recorded at 20 % sucrose concentration for all the mutant lines with line ML-7 (39.70 %) having the highest percentage. Check-1 at 10 % sucrose concentration recorded the least percentage (11.46 %) across the concentration and treatments. Highest pollen diameter (169.52μm) was recorded in Check-1. Suboblate shapes with 10-13 colpi was observed in all the mutant lines and the checks. Pollens from all the lines comprised of circular and elliptic pollens except in ML-7 and the checks where the pollens were solely circular in polar view. The study revealed that gamma-irradiation could be a reasonable tool for inducing variability in sesame and advantageous in increasing the pollen viability.

Effects of sodium azide (SA) and colchicine (COL) (chemical mutagens) on some nutrient compositions of four varieties of sweetpotato (Butter milk, TIS87/0087, UMUSPO/3 and UMUSPO/1) were investigated at the Biotechnology Laboratory of the National Root Crops Research Institute Umudike, Nigeria. The parent plants were treated with sodium azide and colchicine mutagens at concentrations of 0%, 0.03%, 0.05% and 0.07%. Storage roots of the M2V2 generations from the mutant plants were used for the nutrient composition analysis using recommended standard procedures. Nutrient traits studied were: moisture content (%), dry matter content (%), amylose and amylopectin contents (%), starch yield (%), starch content % based on fresh weight and starch content % based on dry weight. Mutants with higher dry matter content than the control were observed in TIS87/0087 treated with SA and COL 0.03%. SA and COL 0.05% produced mutants with higher amylose content (and lower amylopectin) than the control in TIS87/0087. UMUSPO/3 treated with SA 0.03% and SA 0.05% produced mutants with higher values for amylose content (and lower values for amylopectin) than the control; the same variety treated with colchicine (COL 0.05%), recorded higher value for amylose content (and lower value for amylopectin) than the control. These findings showed that sodium azide and colchicine mutagens were potent in inducing variations in nutrient composition of sweetpotato.

The agricultural activities had tremendously benefitted from the application of pesticides. However, various objectionable practices among farmers had exposed the soils, plant and its community of organisms to different level of toxicity. Therefore, this study evaluated the effects of seed coating agents on germination rate, shoot length, leave numbers and population of rhizobial and phosphate solubilizing bacteria (PSB) of beans plant (Vigna unguiculata). The mesocosm experiment was carried out in a greenhouse using a randomized block design with five replicates over the period of 5 weeks. The seed coating agents used were Imidadoprid-Thiram powder formulations and black powdery waste from dry-cell batteries. The seed coating agents were applied at the recommended rate value of 1.25 g/kg and at the rate that double the concentration of recommended field rate (2.50 g/kg). The application of Imidadoprid-Thiram at recommended rate and spent battery waste at the same rate did not have any significant effect (p > 0.05) on the germination of V. unguiculata as compared to the control. However, significant reductions (p < 0.05) in germination were observed in the seed coated with both coating agents at the rate above the recommendation value. Likewise, no significant effect (p > 0.05) of seed coating agents was observed on the average number of leaves of growing V. unguiculata seedling but significant reductions (p < 0.05) were observed in the shoot length of all the treated seedling as compared with control. Both Imidadoprid-Thiram and spent battery wastes were observed to have a significant negative (p < 0.05) effect on the average numbers of both rhizobia and PSB counts in the rhizosphere region of V. unguiculata, with effects more pronounced in higher doses.

Vulnerability assessments to climate change are a possible criterion for adaptation and have a long history on multidisciplinary research. Identification and assessing the degree of vulnerability as a result of climate change is an essential pre-requisite for reducing climate change impacts. The study focuses on vulnerability of rice farmers to climate change in Kogi State, Nigeria. Data for the study were obtained from primary and secondary sources with the aid of structured questionnaire administered to 123 rice farmers from across the four agricultural zones in the State. A total of 15 environmental and socio-economic indicators were identified and analyzed to measure vulnerability status in the agricultural zones. Composite Climate Change Vulnerability Index computed from the hazards, sensitivity and adaptive capacity components revealed that all the rice farmers’ were vulnerable to climate change but vary in the degrees of vulnerability. Scores of Exposure-Sensitivity Index (ESI) suggest that rice farmers in Owolikpa and Igalaogba were most prone and susceptible to climate change whereas, Baganna, Ikande, Odoepe, and Iluke were least exposed and sensitive to climate change. Kpancehe, Kakanda, Girinya, Eggan,and Aiyetoro were categorized under very high to high degree of vulnerability while Iya, Baganna and Echa were rated low vulnerable to climate change. These prioritized areas, based on rank and degree of vulnerability, should be given immediate consideration, and measures should be taken by internalizing region specific needs to address the growing challenge of climate change.