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Maize (Zea mays L.) is one of the most important cereal crops worldwide. However, the grain yield of maize has lagged even as its demand has increased with human population growth. Ecological conditions have significant effects on maize yield. For example, fertile soils could increase the dry matter accumulation of maize, and abundant light and temperature are the basis for high maize yields. Plant density and cropping pattern also exert important effects on the grain yield of cereal crops. This study investigated the growth characteristics, dry matter accumulation (DMA) and distribution, yield, and yield components of maize planted at different densities and with different cropping patterns. Field experiments were conducted in Shehong (SH), Shuangliu (SL), and Yaan (YA) in Southwest China in 2012. Zhenghong 6 was planted at densities of 37,500; 48,750; or 60,000 plants ha-1 in equal or wide-narrow rows with single or double plants per hole. Results showed distinct differences in ecological conditions at the three planting sites. Thus, the plant height, leaf area index (LAI), DMA, and yield of maize were significantly higher in SL than in SH and YA, and the lowest values for these parameters were observed in YA. With increasing plant density, the DMA of each plant decreased, whereas plant height, LAI, and DMA at the population level and yield markedly increased. The highest values for these parameters were consistently correlated with the highest plant density in all experimental sites. In addition, grain yield significantly changed with cropping pattern under limiting conditions. Overall, the results suggested that increasing plant density within a certain range under single and wide-narrow row cultivation is a feasible strategy to increase the grain yield of maize in Southwest China. [ABSTRACT FROM AUTHOR]

Napier grass is a C4 type tropical grass and commonly used as ruminant feedstuffs due to its promising yield. The preservation of Napier grass is to ensure continuous feed supply for the animals during shortage of forages as well as preserving the quality of the grasses. The study on nutritive quality of fresh and ensiled Napier cultivars was conducted at March 2014 at Universiti Putra Malaysia, Malaysia. Four Napier cultivars (Common Napier, Silver Napier, Red Napier and Dwarf Napier) were sown in a randomized complete block design with three replications. The Common, Silver and Red Napier were classified as tall types and Dwarf Napier as short cultivar. Results revealed that Common Napier and Red Napier had significantly higher (P≤0.05) dry matter yield (DMY). Both Silver and Dwarf Napier have the lowest DMY (P≤0.05) regardless of the grass height. Generally, Dwarf Napier had the highest leaf to stem ratio (3.18) and nutritive value (10% crude protein (CP); 66% in-vitro dry matter digestibility (IVDMD); 56% in-vitro organic matter digestibility (IVOMD)) than tall cultivars. The process of fermentation clearly decreased the nutritive value of Napier cultivars. The ensiling process decreased (P≤0.05) neutral detergent fibre (NDF) content (72 to 67%), IVDMD (69 to 61%)and increased (P≤0.05) the IVOMD (52 to 58%) and gross energy (16 to 17 MJ/kg).Regardless of the feed types, the CP content of Napier cultivars surpassed 7% of the minimum requirement for rumen microbial sustainability. There were interaction (P≤0.05) between cultivars and feed types on CP, potential gas production (A+B), metabolisable energy (ME) and degradation rates (C). The CP content of Common, Red and Dwarf Napier increased numerically due to ensiling process. Nevertheless, the ME content and C value declined gradually after the ensiling process. The compaction during ensiling process could affect the quality of Napier cultivars in particular the IVDMD and the degradation rates due to leaching of nutrient. It is concluded that the nutritive value of Napier cultivars were generally decreased due to preservation mechanism. Despite, the CP content and total gas production of Common Napier increased significantly after ensiled. [ABSTRACT FROM AUTHOR]

Nipping is considered to be the cause of increase in seed yield of chickpea. Whether, either morphs of chickpea (Desi & Kabuli) verify this statement or not, an experiment was carried out using twenty chickpea genotypes (11 Desi & 9 Kabuli) and two treatments (nipped, control). Two nippings were carried out with 20-25 days interval. Data analysis revealed highly significant differences among genotypes, treatments and genotype by nipping interaction for yield and yield attributing traits. Eight genotypes viz, NDC-4-20-3, NIFA-2005, Karak-2, SL-3-15, NKC-5-S-12, Karak-1, NDC-15-1 and SL-3-64 revealed positive response to nipping, which also provides green forage. Whereas, twelve genotypes including 3 Desi and 9 Kabuli genotypes showed disincline to nipping. It is concluded that nipping should not be practised without prior testing of its effect on genotypes. Moreover, Desi chickpea respond positively as compare to Kabuli chickpea. Seed yield plant-1 showed highly significant and positive genotypic and phenotypic correlation with secondary branches plant-1 (rg = 0.54,rp = 0.46), pods plant-1 (rg = 0.89,rp = 0.83), seeds pod-1 (rg = 0.58,rp = 54), biological yield plant-1 (rg = 0.97,rp = 0.92), 100-seed weight (rg = 0.52,rp = 0.53), suggesting these traits to be used as selection criteria for yield improvement. [ABSTRACT FROM AUTHOR]

ABSTRACT Breeding material consisted of two parental lines NR371 and 8126 bearing contrasting traits for water stress tolerance, their subsequent generations F1, F2 and their backcrosses BC1, BC2. The experiment was sown under rain shelter to control and avoid any excessive water delivery. Stable performance under both moisture regimes was observed for drought tolerant parent (8126) for almost all the physiological traits. The subsequent generations and backcrosses also gave better results as compared to the susceptible parent (NR371). Moreover, the presence of fixable genetic effects and high heritability estimates for proline content, osmotic potential and canopy temperature were 0.76, 0.71 and 0.70 respectively under water stress regime indicated the use of these traits for breeding stress tolerant varieties. The heritability for leaf carotenoids increased under water stress, contrary to it turgor potential decreased under stress regime. Th7e gene action study of leaf carotenoids and turgor potential is a novel piece of work in this study. Physiological traits are mostly overlooked by the plant breeders in breeding programs having major focus on yield and agronomic variables. The study indicates the possibility of yield enhancement for stress prone areas by breeding physiologically stable and efficient genotypes. [ABSTRACT FROM AUTHOR]

The effects of irrigation and planting pattern on wheat in field conducted at Taian, northern China during 2011-12. The experiments consisted of two planting patterns (single and double rows) and two irrigation levels (0 and 180 mm) resulting in the same plant density (200 × 104 plant/ha). Each experiment plot was 3 m × 3 m in size and replicated thrice in split-plot design. During course of study net photosynthetic rate, H2O conductance, transpiration rate, and maximum photochemical efficiency of flag leaves and grain yield of winter wheat were recorded. At the maturity stage, the net photosynthetic rate of the plants grown in a double-row planting pattern was higher than that of the plants grown in a single-row planting pattern without irrigation. H2O conductance and transpiration rate of plants in the double-row planting pattern were higher than those grown in the single-row planting pattern without and with irrigation. The double-row planting pattern exhibited higher capacity utilization to high light and higher resistivity to photo inhibition than the single-row planting pattern. The spike number per square meter of the double-row planting pattern was higher than that of the single-row planting pattern under the same water treatment. The 1000-kernel weight of the non-irrigated plants grown in the double-row planting pattern was higher than that in the single-row planting pattern. Hence, the double-row planting pattern improved the photosynthetic capacity of winter wheat under water stress (non-irrigated plants). [ABSTRACT FROM AUTHOR]

ABSTRACT: Drought stress at any stage of maize causes a marked reduction in growth and yield formation. Thiourea (TU), a well-known plant growth regulator, can ameliorate the abiotic stress by regulating the crop growth and development; however, little is known regarding its role in improving drought tolerance in maize. Therefore, this study was performed to examine the effectiveness of TU in reducing the negative effects of drought stress on maize crop. The treatments were consisted of three drought levels, control (normal irrigation), skip irrigation at the vegetative stage, and skip irrigation at the reproductive stage, and four TU concentrations, water spray, 400, 800, and 1200 mg L-1. The findings showed that drought stress decreased plant height, cob diameter, grain per cob, chlorophyll content, relative water content (RWC), biological and grain yield, and harvest index. Nonetheless, TU application, particularly at 800 mg L-1, significantly increased plant height, cob and stem diameter, grain per cob, chlorophyll (a and b) and RWC, biological and grain yield, and harvest index. The positive influence of TU application on the growth, yield and yield parameters was remained as 800 mg L-1 > 400 mg L-1 > 1200 mg L-1 > water spray (Figure 4d). In conclusion, TU application at 800 mg L-1 is recommended to mitigate effects of drought stress in maize to get the satisfactory production. [ABSTRACT FROM AUTHOR]

The field investigation entitled "ratooning potential of different sugarcane clones under southern Punjab conditions" was carried out during 2017-18 at Sugarcane Research Station, Khanpur under hot dry agro-climatic conditions of Southern Punjab. The genotypes under investigation were S2008-FD-19, S2008-M-42, S2006-SP-93, S2006-US-321, S2006-US-658, S2008-AUS-133, S2008-AUS-134, S2008-AUS-138, CPF-247 and SPF-234 (Standard). The statistical analysis of the data revealed that new promising sugarcane clone S2008-AUS-133 on account of highest 100-cane weight (105.67 kg), coupled with good stubble sprouting and satisfactory millable cane count, gave maximum stripped cane yield of 104.96 tons ha-1. The top yielder surpassed in quality and as such it fetched maximum sugar yield of 14.33 tons ha-1 followed by SPF-234 (11.76 tons ha-1). The promising sugarcane clone S2008-AUS-133 owing to 11.02 and 21.85 percent more ratoon cane and sugar yield, respectively over the standard variety, is capable of replacing SPF-234. However, its wide scale testing in various agro ecological zones is invited for regional adoptability. [ABSTRACT FROM AUTHOR]