Azarian Journal of Agriculture
Volume:2 Issue: 4, Aug 2015

A field experiment was conducted at National Maize Research Program, Rampur, Chitwan, Nepal during rainy season of 2013 to find out the effect of tillage, residue levels and intercropping systems on yield and yield attributing characters of maize and soybean. The results revealed that the grain yield of maize and soybean was significantly influenced by intercropping systems, but not by tillage system and residue levels. The grain yield of maize obtained under sole cropping (4.76 t/ha) was significantly higher than maize + soybean intercropping system (4.27 t/ha). Similarly, the grain yield of sole soybean was significantly higher (1.99 t/ha) than that of maize + soybean intercropping system (1.26 t/ha). There was 10 percent reduction of maize yield as compared to sole maize system due to intercropping systems. Similarly, reduction of seed yield of soybean under maize and soybean intercropping system was 37 % as compared to sole soybean system. Moreover, the total grain yield equivalent of 6.45 t/ha obtained from sole soybean system was significantly higher and was followed by maize and soybean intercropping system with 4.99 t/ha. Significantly, higher Land Equivalent Ratio (1.38) was recorded with maize and soybean intercropping system over sole system (1.0). Maize and soybean intercropping system produced higher gross return, net return and Benefit: Cost ratio. Net returns and Benefit: Cost ratio obtained from maize + soybean intercropping system under zero tillage residue removed condition was higher of NRs. 1,55,478 and 2.77 respectively.

Twenty one maize genotypes in Intermediate Yield Trial (IYT) and fourteen genotypes in Coordinated Varietal Trial (CVT) were evaluated at Bhagetada, Dipayal, Doti, Nepal in 2012 and 2013 during summer seasons. The trials were laid out in randomized complete block design with three replications. The combined analysis of IYT trials over years showed that Rampur SO3FO8, Across 9531 (RE), RPOP-1 and BLSBSO7-F12 were high yielding genotypes whereas the combined analysis of CVT trials over two years showed that RPOP-3 RPOP-2 and RPOP-4 were high yielding genotypes. The combined analysis of common genotypes (from IYT and CVT) over two years showed that higher grain yielding genotypes were RPOP-1 (3561 kg/ha), RPOP-2 (3464 kg/ha), RPOP-3 (3371 kg/ha) and RPOP-4 (3259 kg/ha).They were promising genotypes however should be tested at on-farms before promoted for general cultivation in river basin agro environment of far western hills of Nepal.

The experiment was conducted at the Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur, Bangladesh during November 2005 to April 2006 to study the seed production potentiality of BSMRAU developed open pollinated radish varieties (viz., BU Mula 1 and BU Mula 2) under two levels of root cutting (viz., one third and no cutup) and three levels of uprooting namely 30, 40 and 50 days after sowing (DAS). Results revealed that both root cutting and uprooting days significantly influenced most of the characters pertaining to seed yield per plant. Root cutting delayed the flowering, pod initiation, maturation of siliqua and reduced plant height, number of branches per plant, number of siliqua per plant, and number of seeds per siliqua. The yields were also impaired by root cutting. In general, the entire yield components and seed yield were highly affected with the one third root cutting. Various uprooting days also had influenced these characters. In case of treatment combination of no cut and 30 days of uprooting there was a significant difference between the varieties. The variety BU Mula 2 produced better seed yield per plot than BU Mula 1. Also in both the varieties the 1/3rd cut treatment with 30 or 50 days uprooting sequence showed unsatisfied number of seeds per siliqua in comparison to the no cut treatment except 40 days uprooting.

The current study was aimed to assess the effects of different iodate concentrations on morpho-physiological characteristics of potato. In this regard, a pot experiment was carried out during the spring and summer 2013. Five concentrations of KIO3 including control beside 10, 20, 40, and 80 mg/Kgsoil were applied through irrigation system. The results showed that all selected agronomical and morphological characteristics of potato except dry weight of stem (SDW) and root (RDW) were negatively affected by high iodate concentrations. The results showed that applying 80 mg KIO3/Kgsoil compared to control resulted in around 15, 86, 84, 41, 16, 25, 20, and 87% reductions in harvest index (HI), leaf dry weight (LDW), tuber dry weight (TDW), plant dry weight (PDW), stem length (SL), root length (RL), plant height (PH), and number of tuber per plant (NT), respectively. Iodate application (80 mg KIO3/Kgsoil vs. control) also affected potato’s physiological characteristics including chlorophyll content (SPAD), relative water content (RWC), water use efficiency (WUE), evapo-transpiration efficiency (ETE), cell membrane stability index (CMSI) and tolerance index (TI) showing around 27, 12, 87, 39, 40, and 77% reductions for each one, respectively. Increasing iodate concentrations, although, showed no effect of Zn concentration of root and Fe and Mn concentrations of leaf, gradually decreased Zn concentration of leaf and increased Fe and Mn concentrations of root and Cu concentrations of root and leaf. Plants also showed several visible symptoms including stunting, chlorosis, browning of leaf tip and reduction in growth due to iodate toxicity.

In order to evaluate the effect of alfalfa extract and plant growth promoting rhizobacteria (PGPR) on growth and uptake of micronutrients in sorghum, a pot experiment was arranged in factorial based on completely randomized design with six replications. The first factor was inoculations (non-inoculated-control and inoculated soil medium with PGPR) and second factor included alfalfa extract concentrations (0, 2 and 4 per thousand). The results showed that by increasing the alfalfa extract, dry weight and uptake of micronutrients such as iron, zinc, manganese and copper increased in shoot of sorghum. Adding PGPR to the soil increased uptake of copper in the plant. Also, alfalfa extract at the level of 4 per thousand and PGPR added to growth medium (soil) significantly increased uptake of manganese in the shoot of sorghum. At the level of 2 per thousand of alfalfa extract, adding these microorganisms to the soil significantly decreased dry weight of sorghum shoot. In general addition of the 0.004 alfalfa extract with PGPR in soil had the best effect on studied parameters.

Root iron (Fe) exclusion capacity of four lowland rice genotypes were evaluated in increasing rate of Fe2+ stresses (0, 500, 1000 and 1500 mg/L) in growing medium under the conditions of low and high vapor pressure deficit. Rice root excluded significantly higher amount of iron under dry atmospheric condition (655 mg Fe/g root dry matter) than moist atmospheric condition (118 mg Fe/g root dry matter). But their iron exclusion capacity reduced when they were gradually exposed to the higher levels of Fe stress. Tolerant genotype such as TOX3107 excluded more iron when they were exposed to dry atmospheric condition.