Effect of promising rice (Oryza sativa L.) varieties and nutrient management practices on growth, development and crop productivity in eastern Himalayas

Abstract

A field experiment was conducted at the Experimental Farm of ICAR-Research Complex for North
Eastern Hill Region, Barapani, Meghalaya during Kharif 2016 to study the effect of promising rice
varieties and nutrient management practices on plant growth, development, and grain and biological
yield of lowland rice in Eastern Himalayas. The experiment was laid-out in split-plot design replicated
thrice consisting of 12 treatment combinations viz. 4 nutrient management practices [100% organic,
100% inorganic (RDF), INM (50% RDF through fertilizers + remaining 50% RDF through FYM and
rock phosphate), and absolute control] in main-plot, and 3 promising rice varieties [Shahsarang-1,
Lumpnah and Megha semi-aromatic-2] in sub-plots. The results showed that the plant height, dry
matter accumulation (DMA), leaf area index (LAI), growth indices like absolute growth rate (AGR),
crop growth rate (CGR), relative growth rate (RGR) and net assimilation rate (NAR) improved
constantly with the succession of crop growth period i.e. 30 to 90 days after transplanting (DAT) as
well as at harvest. Plant height, DMA, LAI, and growth indices in rice crop were observed to be
considerably influenced by different nutrient management practices. Among different nutrient
management practices, significantly higher magnitude of above parameters was found in integrated
nutrient management (INM) practice followed by inorganic practice, organic practice and control,
respectively. Among rice varieties, Shahsarang-1 exhibited higher magnitude of above growth
parameters followed by Lumpnah and Megha SA2, respectively. These rice varieties both under
INM as well as under inorganic practice gave higher amount of growth parameters viz. plant height,
DMA, LAI, growth indices in rice greater than their other counterparts. Grain yield was significantly
higher (4.18 t ha–1) in INM practice followed by inorganic, organic and control treatment. The trend
of grain yield was INM>inorganic>organic>control treatment, respectively. Similar trend was also
observed for biological yield. Among rice varieties, Shahsarang-1 produced significantly highest
grain yield (3.86 t ha–1) followed by Lumpnah (3.60 t ha–1) and Megha SA2 (3.19 t ha–1), respectively.
Similar trend was also observed for biological yield. In nutshell, INM practice (50% RDF through
fertilizers + remaining 50% RDF through FYM and rock phosphate) is the best nutrient management
technology to harness better growth and crop productivity in eastern Himalayas. Similarly,
Shahsarang-1 was the best performer in terms of growth and crop productivity over other two
promising rice varieties viz. Lumpnah and Megha SA2 in north-eastern Himalayan region.