Effect of Rice straw compost and mineral fertilizers on yield and nutrient uptake by Indian mustard in saline soil

Abstract

We investigated the effect of rice-straw compost (RSC) with and without mineral fertilisers on yield of Indian mustard
(Brassica juncea L.) and chemical properties of saline soil. A field experiment was conducted for three consecutive years
during 2012–15. Treatments consisted of control (cont), recommended dose of N:P:K fertilizers at 60:30:30 kg ha-1 (100%
RDF), rice straw compost at 14 t ha-1 (RSC-14) and RSC@ 7 t ha-1 + 50% RDF (RSC+RDF) laid out in randomized block
design with three replication. Integrated use of RSC+RDF produced in 13 and 16% mean of (3 year) grain and straw yield
respectively, over the alone use of 100% RDF. RSC had higher grain yield of mustard as compared to 100%RDF, however,
it was statistically at par with 100%RDF. Significantly higher grain (23.1 q ha-1) and straw (61.2 q ha-1) yield was observed
with RSC+RDF than other treatments except RSC. Higher NPK uptake by mustard grain and straw was registered under
100%RDF than cont. Significant build-up of soil fertility in terms of available nitrogen (N) and potassium (K) was
maintained with RSC+RDF as compared to cont. Soil treated with 100%RDF had 56 and 37% higher available N and K
respectively, over cont. Soil organic carbon (SOC) was significantly influenced with integration of RSC+RDF than 100%
RDF. Treatment receiving RSC-14 had 18% higher SOC than 100% RDF. The magnitude of changes in electrical conductivity
(EC) was at par among the treatments, though lowest soil EC was reported with integrated use of compost and mineral
fertilizers. Our results highlight that combined use of RSC (RSC-7) and mineral fertilizers (50% RDF) is beneficial option
for improving mustard yield and fertility of saline soils.