Soil physico-chemical characterization in the different soil layers of National Maize Research Program, Rampur, Chitwan, Nepal

Soil pit digging and their precise study is a decision making tool to assess history and future of soil management of a particular area. Thus, the present study was carried out to differentiate soil physico-chemical properties in the different layers of excavated pit of the National Maize Research Program, Rampur, Chitwan, Nepal. Eight pits were dug randomly from three blocks at a depth of 0 to 100 cm. The soil parameters were determined in-situ, and in laboratory for texture, pH, OM, N, P (as P2O5), K (as K2O), Ca, Mg, S, B, Fe, Zn, Cu and Mn of collected soils samples of different layers following standard analytical methods at Soil Science Division, Khumaltar. The result revealed that soil structure was sub-angular in majority of the layers, whereas bottom layer was single grained. The value and chrome of colour was increasing in order from surface to bottom in the majority pits. Similarly, the texture was sandy loam in majority layers of the pits. Moreover, four types of consistence (loose to firm) were observed. Furthermore, mottles and gravels were absent in the majority layers. Likewise, soil was very to moderately acidic in observed layers of majority pits, except bottom layer of agronomy block was slightly acidic. Regarding fertility parameters (OM, macro and micronutrients), some were increasing and vice-versa, while others were intermittent also. Therefore, a single layer is not dominant for particular soil physico-chemical parameters in the farm. In overall, surface layer is more fertile than rest of the layers in all the pits.

Climate change and maize agriculture among Chepang communities of Nepal: A review

This paper reviews recent literature concerning effects of climate change on agriculture and its agricultural adaptation strategies, climate change impacts on Chepang communities and their maize farming. Climate change is perhaps the most serious environmental threat to agricultural productivity. Change in temperature and precipitation specially has greater influence on crop growth and productivity and most of these effect are found to be adverse. Climate change has been great global threat with global temperature rise by 0.83 °C and global sea level rise by 0.19 m. Poor countries of the world are more vulnerable to changing climate due to different technological, institutional and resource constraints. In context of Nepal, practices like tree plantation, lowering numbers of livestock, shifting to off farm activities, sloping agricultural land technology (SALT) and shifting cultivation are most common coping strategies. Chepang, one of the most backward indigenous ethnic groups of Nepal are also found to perceive change in the climate. Perception and adaptation strategies followed by different farmers of world including Chepang is mainly found to be effected by household head’s age, size of farm, family size, assessment to credit, information and extension service, training received and transportation. Maize is second most important crop in Nepal in which increase in temperature is favorable in Mountain and its yield is negatively influenced by increase in summer rain and maximum temperature. Local knowledge of indigenous people provides new insights into the phenomenon that has not yet been scientifically researched. So, government should combine this perceptive with scientific climate scenario and should conduct activities in term of adoption strategies and policies to insist targeted and marginalized farmers.

Analysis of genetic diversity among the maize inbred lines (Zea mays L.) under heat stress condition

High temperature adversely affects the plant physiological processes: limits plant growth and reduction in grain yield. Heat stress is often encountered to spring sowing of maize in spring season. Twenty maize inbred lines were studied for days to 50 % anthesis and silking, anthesis–silking interval, leaf firing, tassel blast, SPAD reading and leaf senescence, plant and ear height, leaf area index, ear per plant, cob length and diameter, number of kernel/ear, number of kernel row/ear, number of kernel row, silk receptivity, shelling percentage, thousand kernel weight and grain yield in alpha lattice design at National Maize Research Program at Rampur, Chitwan,Nepal with the objective to identify superior heat stress tolerant lines. Analysis of variance showed significant difference for all the traits. Result of multivariable analysis revealed that twenty inbred lines formed four clusters. The resistance inbred lines and susceptible inbred lines formed different clusters. The members of cluster 4 were found to be tolerant to heat stress due to they had lowest value of tassel blast, leaf firing, and leaf area index with highest value of cob diameter and length, ear per plant, number of kernel row/ear, number of kernel/ear, number of kernel row, shelling percentage, silk receptivity and grain yield whereas as members of cluster 1were found most susceptible due to they had longer anthesis silking interval, with maximum tassel blast and leaf firing along with no grain yield under heat stress condition. From this study inbred lines RL-140, RML-76, RML-91 and RML-40 were found most tolerant to heat stress. These inbred lines belonging to superior cluster could be considered very useful in developing heat tolerant variety and other breeding activities.

Technical efficiency of certified maize seed in Palpa district, Nepal: A stochastic frontier production approach

The cereal crop, maize is regarded as staple food mainly in hill areas of Nepal. Seed is one of the vital input which determines the production and yield of any crop. Farmers are found using the required inputs in haphazard way which had increased the cost of production and inefficiency of resources used. The study on seed sector is limited. For such a backdrop, this study was aimed to assess the level of technical efficiency (TE) of certified maize seed production. The total of 164 certified seed producer were interviewed in June, 2016 using simple random sampling technique in Palpa district of Nepal. The result revealed that increase in amount of seed and labor by one percent would increase the yield of certified maize seed by 0.29 and 0.34 percent respectively. The TE was estimated using stochastic production frontier model in Stata software. The average TE was found 70 percent which revealed the scope of increasing TE by 30 percent using the existing available resources. There were about 29 percent farmers who had TE of ≥0.7-0.8 followed by 27.44 percent at ≥0.8-0.9. Government and other stakeholders should prioritize to provide technical knowledge via training and increase the visit of extension worker to increase TE of certified maize seed producer in the district.

Evaluation of early maize genotypes for grain yield and agromorphological traits

The purpose of this study was to assess the variation on agro-morphological traits and grain yield. A set of 14 early maize genotypes were studied at research field of Regional Agricultural Research Station (RARS), Doti, Nepal in summer seasons of 2015 and 2016. The experiment was carried out in Randomized Complete Block Design (RCBD) with three replications in each year. The variation among genotypes was observed for grain yield and flowering. The genotype SO3TEY-PO-BM produced the highest grain yield (4.33 t/ha) in 2015 whereas Rajahar Local Variety produced the highest grain yield (2.52 t/ha) in 2016. The combined analysis over years showed that Farmer’s variety was found earlier in tasseling (36 days) and silking (39 days), followed by S97TEYGHAYB(3) in tasseling (45 days) and by S97TEYGHAYB(3) and Arun-4 in silking (48 days). EEYC1 produced the highest grain yield (3.17 t/ha), followed by COMPOL-NIBP (3.09 t/ha), SO3TEY-PO-BM (2.90 t/ha), S97TEYGHAYB(3) (2.78 t/ha) and Rajahar Local variety (2.77 t/ha), respectively. The information on variation for the agro-morphological traits among studied early maize genotypes will be helpful to plant breeders in constructing their breeding materials and implementing selection strategies.

Performance evaluation of locally developed black light trap for maize insects monitoring in Chitwan, Nepal

Till today, the light traps in Nepal are found using with traditional type, which have not being recognized internationally. These light traps were of low efficiency for trapping insects as compared to black light trap (BLT). The black light tube (F10T8/BL) was used in newly constructed trap at National Maize Research Program (NMRP), Rampur, Chitwan, Nepal. Both traps were installed at the maize experimental field at NMRP during February to October, 2017. Data on insect numbers were recorded once in a week from dusk to down in two different days to minimize the light effects of each others. The total number of insects trapped in BLT was 2804 as compared to 868 in traditional light trap (TLT). Among the insect orders, Coleopterans were mostly trapped in BLT followed by Lepidopteron and Hemipterans. The results showed that the trapping efficiency of BLT was three fold higher than that of TLT. Therefore, black light trap was highly effective monitoring tool and its field applications are expected to be commercialized.

Socio-economic assessment on maize production and adoption of open pollinated improved varieties in Dang, Nepal

Research was conducted from February to May, 2017 for socioeconomic assessment on maize production and adoption of open pollinated improved maize varieties in Dang district of Nepal. Altogether, 100 samples were taken by simple random sampling from the major maize growing areas and relevant publications were reviewed. Focal Group Discussion and Key Informant Survey were also done. Descriptive statistics, unpaired t-test, probit regression and indexing were used for data analysis using statistical tools- SPSS, STATA and MS-Excel. Probit econometric model revealed that ethnicity (1% level), gender (5% level), area under open pollinated improved maize (1% level), seed source dummy (1 % level) and number of visits by farmers to agrovet (5% level) significantly determined the adoption of open pollinated improved maize varieties. In addition, unpaired t-test revealed that the productivity of open pollinated improved maize varieties was significantly higher (at 1% level) than local; also, the multinational companies' hybrids showed significantly higher productivity (at 1% level) when compared to open pollinated improved varieties. Furthermore, indexing identified- lack of availability of quality seeds and fertilizers (I= 0.86) as the major problem associated with the maize production. Giving aggressive subsidy on open pollinated improved seeds and dealership to registered agrovets for selling the subsidy seeds could enhance the adoption. Moreover, government organizations working in the areas of agricultural extension and research must focus on adoption of open pollinated improved maize varieties among the farmers, substituting the local and developing the high yielding hybrid varieties in Nepal to increase the maize productivity.

Screening of promising maize genotypes against maize weevil (Sitophilus zeamais Motschulky) in storage condition

The maize weevil (Sitophilus zeamais Motschulsky) is a serious pest of economic importance in stored grains. It causes major damage to stored maize grain thereby reducing its weight, quality and germination. An experiment was conducted in randomized complete block design (RCBD) with 3 replications to screen 32 maize genotypes against maize weevil in no-choice and free-choice conditions at Entomology Division, Khumaltar, Lalitpur (Room temperature: Maximum 24-32°C and Minimum 18-27°C). The findings showed that the maize genotypes had different response to maize weevil damage ranging from susceptible to tolerance. The genotypes Manakamana-3, Lumle White POP Corn and Ganesh-2 showed their tolerance to S. zeamais as evidenced by lower number of weevil emerged/attracted, lower amount of grain debris release and lower proportion of bored grains, while the genotype ZM-627 was the most susceptible to weevil damage in both tests. The other remaining genotypes were intermediate types. This information is useful to improve grain protection in storage and varietal improvement/release program.

Effects of storage structures and moisture contents on seed quality attributes of quality protein maize

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 (R2=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.

Comparative study of impact of Azotobacter and Trichoderma with other fertilizers on maize growth

Biofertilizers may be a better eco-friendly option to maintain soil fertility. The study was conducted to investigate the effect of Azotobacter and Trichoderma on the vegetative growth of maize (Zea mays L.) plants. The experiment was carried out in medium sized pots, at IAAS, Lamjung (Feb 2017 - May 2017) in completely randomized design (CRD), consisting eight treatments and three replications. Treatments were namely T1 (control), T2 (Azotobacter), T3 (Trichoderma), T4 (Azotobacter + Trichoderma), T5 (NPK), T6 (Azotobacter + Trichoderma + FYM), T7 (Azotobacter + Trichoderma + FYM + NPK), T8 (FYM). Azotobacter showed a positive increase in plant height, stem girth, dry shoot weight, root length and width, and root weight while Trichoderma displayed either negative or minimal impact. Effect of FYM was lower than Azotobacter but considerably higher than Trichoderma. Trichoderma seriously inhibited the expression of Azotobacter when used together. Trichoderma even suppressed the outcome (except shoot weight) of FYM when used together. Root length was the longest in Azotobacter inoculation. The highest number of leaves was in T7 followed by Azotobacter (T2) and NPK (T5). Unlike leaf width, Azotobacter showed a negligible increase in leaves length while Trichoderma wherever present showed the negative impact. Minimum chlorophyll content was found in Azotobacter or Trichoderma after 73 days. Azotobacter treatment showed early tasseling than Trichoderma. The association of Azotobacter and Trichoderma increased the biomass. Azotobacter has significant effects on growth parameters of maize and can supplement chemical fertilizer, while Trichoderma was found to inhibit most of the growth parameters.