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The study was aimed to examine the effects of various storage structures and moisture contents on seed quality attributes of quality protein maize seed. The quality protein maize (QPM-1) seed was tested in conventional seed storage containers (Fertilizer sack and earthen pot) and the improved hermetic ones (Metal bin, Super grain bag, and Purdue Improved Crop Storage (PICS) bag) at Seed Science and Technology Division, Khumaltar, Nepal during February, 2015 to January 2016. Ten treatments comprising 5 storage devices in two moisture regimes (11% and 9%) replicated thrice and laid out in Completely Randomized Design (CRD). Data on temperature, relative humidity (RH), germination, electrical conductivity (EC), seed moisture content (MC) were collected bimonthly. The conventional containers were found liable to the external environmental condition whereas the hermetic structures observed with controlled RH level below 40% in all combinations. Electrical conductivity (EC) for seed vigor showed that hermetic containers provide higher seed vigor than the conventional ones. Up to 4 months all treatments were found statistically at par for germination. A significant difference was observed in each treatment after 4 months where PICS bag & Super grain bag showed best germination followed by metal bin while fertilizer bag & earthen-pot showed poorer and poorest germination respectively till one year. Almost all treatments with lower MC showed better results than the treatments with higher MC. A negative correlation (R 2 =69.7%) was found between EC and Germination. All six figures from 2 to 12 months on MC showed statistically different where hermetic plastic bags were found maintaining MC as initial whereas MC of fertilizer bags and earthen pot was spiked than the basal figure. The finding evidenced that the hermetic containers and low MC are the seed storage approaches for retaining the quality of seed even in an ambient environmental condition for more than a year.Keywords: Seed quality, Germination, storage containers, Electrical conductivity, Moisture content 78 INTRODUCTIONMaize (Zea mays L.) is the second most important staple food crop after rice and a major feed crop in Nepal (KC et al., 2015). Despite the implementation of various seed related projects and active involvement of public and private institutions; still the country has been suffering from unavailability of quality seeds. Quality seed demand in Nepal is apparently tremendous, where lion's share of seeds are imported and country's import has been hiking each year. The official record of Seed Quality Control Centre (SQCC) in 2015 shows that 2745 metric tons of seed was traded in where 1025 million of Nepalese currency redeemed. Formal sector contributes less than 10% of seed demand whereas Informal sector, farmer-to-farmer seed exchange mechanism has been contributing 20-50% of seed demand. Seed replacement rate (SRR) for maize is below 15 % (Joshi, 2015). Hence, production and proper storage of quality seed in community level is regarded as p...

Maturity traits such as days to heading and days to physiological maturity have a large impact on agronomic characteristics of wheat (Triticum aestivum L.) cultivars grown in specific environments. Extended green leaf and green glume duration after heading in hard red spring wheat have been shown to result in longer grain‐fill duration, increased kernel weight, and higher grain yield in dry environments. The genetic relationship between maturity traits, seed quality, and functional bread‐making characteristics was investigated for three sets of recombinant inbred lines derived from crosses between hard red spring wheat parents. Early heading date was correlated with increased seed quality as indicated by test weight and kernel weight in all three genetic populations. Days to heading was not consistently correlated with functional quality related to bread‐baking. Longer green glume and green leaf duration after heading were typically positively related to seed quality traits including test weight and kernel weight in the three populations. However, increased green leaf and green glume duration after heading were often negatively correlated with functional quality parameters related to bread baking. Our results suggest that selection for long green leaf or green glume duration after heading to stabilize grain yield in a warmer climate may also result in a decrease in bread‐making potential.

Six maize hybrids; Khumal Hybrid-2, KML-5(A) × KYM-33, KML-8(A) × KYM-33, KWM-91 × KWM-93, KWM-92 × KWM-93, Super-951 were evaluated in a randomized complete block design (RCBD) with three replications at Bhotechaur (Sindhupalchowk), Mandan Deupur (Kavrepalachowk), and Khumaltar (Lalitpur), Nepal to identify stable and superior hybrids. Hybrids were found significant (p<0.01) for grain yield. The effects of environment and genotype × environment (G × E) interactions on grain yield were found to be significant (p<0.01). The combined analysis showed that KWM-91 × KWM-93 produced the highest grain yield (8.89 t ha-1) across all locations, followed by KWM-92 × KWM-93 (8.60 t ha-1), which was at par with each other. The hybrids; KWM-92 × KWM-93 (bi=0.84, CV=18.54%, SD=1.59) and KWM-91 × KWM-93 (bi=1.16, CV=22.37 %, SD=1.99) were found to be more stable, with regression coefficient (bi) nearly equal to unity (1) and grain yields above the grand mean yield. The GGE biplot revealed that KWM-91 × KWM-93 was the most responsive hybrid for Mandandeupur and Bhotechaur environments; whereas, KWM-92 × KWM-93 was for the Khumaltar environment. Hybrid KWM-91 × KWM-93 was the most stably yielding hybrid among all hybrids. This study suggests that KWM-91 × KWM-93 can be promoted for cultivation in mid hills of Nepal. SAARC J. Agric., 19(2): 107-121 (2021)

Hard red spring wheat (Triticum aestivum L.) grown in rainfed environments in the northern Great Plains of North America frequently encounter drought and heat stress during grain-fill, thus reducing yield. Delayed leaf senescence after heading, known as the stay-green trait, has been found to help spring wheat tolerate drought and heat stress during grain-fill. To better understand how the staygreen trait relates to expression of other agronomic traits, data was analyzed from a recombinant inbred line (RIL) population derived from a 'Vida'/MTHW0202 cross grown in rainfed and irrigated environments. The genetic architecture controlling traits measured in this study were also examined. Results found the stay-green trait was significantly correlated to overall yield (P < .001, r = .37) in rain-fed environments, but was not significantly correlated to yield (P = .26, r = .09) in irrigated environments. Three quantitative trait loci (QTL) located on chromosomes 2D, 4A, and 4D were associated with the stay-green trait. The 4A stay-green QTL, previously designated QGfd.mst-4A, was collocated with QTL for seed number per head, thousand kernel weight, and heading date. The 4D staygreen QTL overlaps the Rht-D1 plant height gene, and the allele prolonging the stay-green period co-segregates with the wild-type (tall) Rht-D1a allele. Results from this study provide a better understanding of the relationship between staygreen and agronomic traits in rainfed vs. irrigated environments. Additionally, understanding the genetic architecture controlling stay-green and agronomic traits will aid in selecting future drought-tolerant spring wheat varieties. 1 INTRODUCTION Drought and heat stress during hard red spring wheat (Triticum aestivum L.) grain-fill decreases yield in rain-Abbreviations: cM, centimorgan; GLDAH, green leaf duration after heading; QTL, quantitative trait loci; RIL, recombinant inbreed lines; SNP, single nucleotide polymorphism; SSD, single seed descent. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

A field experiment was conducted at the Agronomy farm of Institute of Agriculture and Animal Science (IAAS), Rampur during winter season of 2014/2015 to find out the response of wheat varieties under different sowing dates. There was 9 treatments consisting three date of sowing (November 14, November29 and December 14) in main plot and three varieties namely Tillotama, Danfe and Vijay in sub-plot and were arranged in split plot design with three replications. The grain yield was significantly higher (3.09 tha -1 ) at November 14 whereas highest straw yield was recorded for November 29 sown wheat (5.61 t ha -1 ). Effective tiller (414) and number of grain per spike (34.34) were highest for November 29 sown wheat. The late sown wheat had more sterile floret (42.65%) while early sown wheat had highest thousand grain weight (51.23 g). Danfe had highest straw yield (5.87 t/ha). Effective tiller/m 2 (419) and sterility percentage (43.35%) of Danfe was highest. Number of grains per spike (37.89) of Tillotama was highest and thousand grain weight (57.09 g) of Bijay was found highest. The grain yield of Bijay (3.30tha -1 ) was highest when it was sown at November 29.

A field experiment with three wheat varieties at different sowing dates on two crop establishment methods was accomplished to identify the optimum sowing date at AFU Rampur during winter season of 2014/2015. Three wheat varieties namely: Tillotama, Danfe and Vijay sown on three dates: 14 th November, 29 th November, and 14 th December under two crop establishment practices: Conservational and conventional agriculture were evaluated with strip -split plot design in three replications. The field data on yield attributes and yields were collected. Earlier sowing on 14 th November gave the highest yield (3427.15 kg ha -1 ), total dry matter (8154.44 kg ha -1 ), with longest days to crop maturation (133.11 days). In case of varieties, Vijay gave the highest grain yield (3458.61 kg ha -1 ) and total dry weight (4456.11 and 8832.42 kg ha -1 respectively) with earliest days to heading and maturity. The straw yield was the highest for 29 th November sowing (5821 kg ha -1 ) and for Danfe variety (5756 kg ha -1 ). Vijay variety recorded the highest thousand grains weight (43.60 g) and highest harvest index (35.89%) even though with the lowest effective tillers per square meter (320.83), it proved to be the most promising variety.

Stability analysis identifies the adaptation of a crop genotype in different environments. The objective of this study was to evaluate promising rice genotypes for yield stability at different mid-hill environments of Nepal. The multilocation trials were conducted in 2017 and 2018 at three locations viz Lumle, Kaski; Pakhribas, Dhankuta; and Kabre, Dolakha. Seven rice genotypes namely NR11115-B-B-31-3, NR11139-B-B-B-13-3, NR10676-B-5-3, NR11011-B-B-B-B-29, NR11105-B-B-27, 08FAN10, and Khumal-4 were evaluated in each location. The experiment was laid out in a randomized complete block design with three replications. The rice genotype NR10676-B-5-3 produced the highest grain yield (6.72 t/ha) among all genotypes. The growing environmental factors (climate and soil conditions) affect the grain yield performance of rice genotypes. The variation in climatic factors greatly contributed to the variation in grain yield. Polygon view of genotypic main effect plus genotype-by-environment interaction (GGE) biplot showed that the genotypes NR10676-B-53 and NR11105-B-B-27 were suitable for Lumle; NR11115-B-B-31-3 and NR11139-B-B-B-13-3 for Pakhribas; and 08FAN10 and NR11011-B-B-B-B-29 for Kabre. The GGE biplot showed that genotype NR10676-B-5-3 was stable hence it was near to the point of ideal genotype. This study suggests that NR10676-B-5-3 can be grown for higher grain yield production in mid-hills of Nepal.