Azarian Journal of Agriculture
Volume:3 Issue: 4, Aug 2016

The germination of sweet pepper (Capsicum annuum L.) seeds by hydropriming and osmopriming was investigated. Treatments comprised immersion in different polyethylene glycol (PEG6000) solutions ranging from -1.0 to -1.5 MPa, soaking in distilled water, and unprimed (control). Seeds were soaked for 7 and 14 days at 15±2 degree Celsius, and then seed quality was tested germination in the laboratory and the greenhouse. A completely randomized design was used with three replications. When the seeds were osmoprimed in -1.5 MPa for 14 days, the highest germination percentage, plant height, number of roots and root length were obtained at both of the conditions. Furthermore, there were no abnormal seedlings in this treatment. Thus, this method is the most suitable for farmers to increase the germination percentage, germination index, and homogenous emergence of sweet pepper seeds under a wide range of environments.

Globally, it is well debated fact that the water productivity in agriculture needs to be raised in order to meet the increasing demand for the feed and food production, which will double by 2050. Simulation models have been developed for predicting the effects of soil, water and nutrients on growth and water productivity of different crops. In this study, AquaCrop model was calibrated for grain maize (Single Cross 260) using drip irrigation system under varying irrigation and nitrogen levels. The intervals of irrigation were 6 days (F1), 12 days (F2) and 18 days (F3) which combined with different nitrogen levels of 0 (N1), 120 (N2), 180 (N3) and 240 kg ha-1. Root Mean Square Error (RMSE), normalized Root Mean Square Error (RMSEn), Mean Absolute Error (MAE), Prediction error (Pe) and coefficient of determination (R2) were used to test the model performance. The model was calibrated for simulating maize grain and biomass yield for all treatment levels with the prediction error 0.37<Pe<1.5 percent, 0.87<R2<0.92 and 0.8<RMSE<1.37 t ha-1. The results of the study showed that the AquaCrop model simulated aboveground biomass and grain yield in normal conditions more accurately than moderate and severe water stress conditions.

An inheritance study in the inter-specific cross of O. sativa × O. rufipogon was conducted in the greenhouse of the Institute of Agriculture and Animal Science (IAAS), Rampur, Chitwan, including the parents, F1 and subsequent F2 segregants. In the parent as O. sativa a local landrace Pokhreli pahele was used. A dominant gene action was observed for the procumbent growth habit, awnedness, and higher spikelet shattering. Awnedness was found to be governed by three genes with the duplicate gene action (63:1.). Digenic complementary gene action was observed for culm angle (9 procumbent: 7 erect) and digenic polymeric gene action for spikelet shattering (9 highly shattering: 6 intermediate shattering: 1 low shattering).

A field experiment was conducted, to evaluate the yield and yield attributes of drought tolerant rice (Oryza sativa L.) varieties under different planting geometry in Narayani-7, Nawalparasi from May to November, 2014. The experiment was carried out in two factor Randomized Complete Block Design with three replications consisting three rice varieties (Sukhadhan-4, Sukhadhan-5 and Radha-4) and four planting geometry (15 cm × 10 cm, 15 cm × 15 cm, 20 cm × 15 cm and 20 cm × 20 cm). The results revealed that the highest grain yield (6.5 t ha-1) was obtained from plant spacing 20 cm ×15 cm with highest number of effective tillers m-2 (342.6) and highest harvest index (44.8%) while, number of filled grains panicle-1 and panicle length was found statistically at par with 20 cm × 20 cm and 20 cm × 15 cm planting geometry. However, the straw yield and test weight were non-significant with different planting geometry. Regarding tested varieties, Sukhadhan-5 produced highest grain yield (6.1 t ha-1) with highest number of effective tillers (337 m-2), more number of filled grain panicle-1 (144) and more harvest index (44%) compared to other tested varieties in the experiment. The Sukhadhan-4 recorded the longest panicle (28.5 cm) while Radha-4 produced significantly highest straw yield (8.1 t ha-1). Thus, Sukhadhan-5 with 20 cm × 15 cm spacing seems more economical and profitable to grow in rainfed lowland ecosystem in Terai and inner Terai areas of Nepal.