Source Of Nutrient Supply Research Articles

Promotion of the growth and yield of Zea mays by synthetic microbial communities from Jala maize.

Plant growth-promoting bacteria (PGPB) are a source of nutrient supply, stimulate plant growth, and even act in the biocontrol of phytopathogens. However, these phenotypic traits have rarely been explored in culturable bacteria from native maize landraces. In this study, synthetic microbial communities (SynCom) were assembled with a set of PGPB isolated from the Jala maize landrace, some of them with additional abilities for the biocontrol of phytopathogenic fungi and the stimulation of plant-induced systemic resistance (ISR). Three SynCom were designed considering the phenotypic traits of bacterial strains, including Achromobacter xylosoxidans Z2K8, Burkholderia sp. Z1AL11, Klebsiella variicola R3J3HD7, Kosakonia pseudosacchari Z2WD1, Pantoea ananatis E2HD8, Pantoea sp. E2AD2, Phytobacter diazotrophicus Z2WL1, Pseudomonas protegens E1BL2, and P. protegens E2HL9. Plant growth promotion in gnotobiotic and greenhouse seedlings assays was performed with Conejo landrace; meanwhile, open field tests were carried out on hybrid CPL9105W maize. In all experimental models, a significant promotion of plant growth was observed. In gnotobiotic assays, the roots and shoot length of the maize seedlings increased 4.2 and 3.0 times, respectively, compared to the untreated control. Similarly, the sizes and weights of the roots and shoots of the plants increased significantly in the greenhouse assays. In the open field assay performed with hybrid CPL9105W maize, the yield increased from 11 tons/ha for the control to 16 tons/ha inoculated with SynCom 3. In addition, the incidence of rust fungal infections decreased significantly from 12.5% in the control to 8% in the treatment with SynCom 3. All SynCom designs promoted the growth of maize in all assays. However, SynCom 3 formulated with A. xylosoxidans Z2K8, Burkholderia sp. Z1AL11, K. variicola R3J3HD7, P. ananatis E2HD8, P. diazotrophicus Z2WL1, and P. protegens E1BL2 displayed the best results for promoting plant growth, their yield, and the inhibition of fungal rust. This study demonstrated the biotechnological eco-friendly plant growth-promoting potential of SynCom assemblies with culturable bacteria from native maize landraces for more sustainable and economic agriculture.

Impact of fodder grasses and organic amendments on productivity and soil and crop quality in a subtropical region of eastern Himalayas, India

Agriculture in the Eastern Indian Himalayas is characterized by fragility and marginality with about 77% of the geographical area under hills and degraded plateau. Thus, field experiments were conducted for three consecutive years during 2008–2011 to assess the impact of perennial fodder grasses and sources of nutrient supply on productivity and quality of soil and fodder under terrace conditions in a subtropical degraded hill soil of Meghalaya, India (980m above sea level). The treatment consisted of four fodder crops and three sources of nutrients. Fodder crops were broom grass (Thysanolaena maxima), congosignal grass (Brachieria rosenesis), hybrid napier (Pennisetum typhoides x P. purpureum) and guinea grass (Panicum maximum). Three sources of nutrient supply were organic, inorganic and control (inherent soil fertility conditions). Farmyard manure (FYM) was used as organic source of nutrient supply on N equivalent basis and P nutrition was supplemented through rock-phosphate. Fertilizer urea, single super phosphate and muriate of potash were used as inorganic source of nutrients. The dry fodder yield increased in each successive year and three year average dry fodder yield was significantly higher with hybrid napier (28.1Mgha−1) than other grasses. Among nutrient sources, the average dry fodder yield under organic amendment (22.9Mgha−1) was 27.5 and 64.4% higher than that under inorganic fertilizer (17.9Mgha−1) and control (13.9Mgha−1), respectively. Crude fibre (35.9%) and lignin (7.02%) concentrations were the maximum in hybrid napier whereas, cellulose (39.1%) was the highest in congosignal grass. On the contrary, crude protein concentration was the maximum in broom grass (8.27%), and it was at par with that in hybrid napier. The available N, P, K and soil organic carbon (SOC) contents were significantly higher (P=0.05) under organic compared to those under other nutrient sources. The SOC concentration (17.2gkg−1) and stock (32.2Mgha−1) after three years under organic treatment was 5.3 and 2.1% and 13.3 and 8.1% higher than that recorded under inorganic and control, respectively. The study indicated suitability of fodder grasses and organic amendments in improving quality of marginal degraded hill soils.

Influence of cropping systems and organic amendments on productivity and soil health at mid altitude of North East India

Field experiments were conducted during 2006-07 to 2008-09 to assess the response of different cropping systems and organic amendments on productivity and soil health at mid altitude (950 m MSL) of Meghalaya. The treatments consisted of two rice based (rice (Oryza sativa L.) + soybean [Glycine max (L.) Merr.] - rapeseed, rice + soybean - tomato (Solanum lycopersicum L.) and two maize based (maize (Zea mays L.) + soybean - groundnut (Arachis hypogaea L.), maize + soybean- French bean (Phaseolus vulgaris L.)) cropping systems and five organic amendments, viz. farmyard manure (FYM), vermicompost (VC), local compost (LC), combined sources of nutrient (1/3 FYM +1/ 3 VC + 1/3 LC) and control (no manure) as sources of nutrient supply. Organic manures were applied on N-equivalent basis and phosphorus requirement was compensated through rock phosphate. The results revealed that the yield of different crops were maximum under combined sources of nutrient supply (CSN). Pooled (3 years) maize equivalent yield (MEY) was the highest under FYM followed by CSN and remained at par with each other. The pooled MEY under FYM and CSN were 171 % and 162 % higher than control, respectively. Among the cropping systems, maize + soybean - French bean recorded the highest MEY (28.78 t/ha). Total N, P and K uptake was maximum with CSN and remained similar with FYM. Maximum bulk density, soil organic carbon, soil microbial biomass carbon, dehydrogenase enzyme activity, available N and K in soil after three cropping cycles were also recorded under CSN. Maize + soybean - French bean cropping system along with FYM as source of nutrient supply was found to be cost effective with optimum productivity during transition to organic farming.

Synergistic association of Rhizobium with phosphate-solubilizing bacteria under different sources of nutrient supply on productivity and soil fertility in soybean (Glycine m u )

A field experiment was conducted during the summer and rainy seasons of 1999 and 2000 to study the effect of Rhizobium and phosphate-solubilizing bacteria (PSB) on growth, yield, nutrient uptake and soil fertility of soy- bean [Glycine max (L.)' Merr.] under different sources of nutrient supply (vermicompost, pressmud and composted coir pith, each at 75 and 100% N substitution and inorganic fertilizers. Association between Rhizo- bium and phosphate-solubilizing bacteria was synergistic and their dual inoculation improved the seed yield of soybean significantly (30.9 and 33.6%) over untreated control during summer and rainy seasons respectively. Significant increase in NPK uptake and post-harvest soil N and P levels was observed under combined inocula- tion of biofertilizers. Among the sources of nutrient supply, vermicompost at 75% N substitution excelled all oth- ers in improving the growth and seed yield of soybean. Organic manures tried at 75% N substitution gave higher seed yield than 100% N substitution. Application of organic manures resulted in desirable post-harvest soil sta- tus with more N and P.

A comparison of two grassland‐based systems for autumn‐calving dairy cows of high genetic merit

A full lactation study compared the performance of autumn‐calving dairy cows of high genetic merit under two contrasting systems of milk production: high forage (HF) and high concentrate (HC). During the winter, animals on system HF were offered a silage with a high feeding value characteristics, supplemented with 5·5 kg of concentrate [crude protein content of 280 g kg−1 dry matter (DM)] through an out‐of‐parlour feeding system. From 14 March, these animals were given increasing access to grazing, achieving 24‐h turnout on 15 April. Thereafter, until day 305 of lactation, these animals were offered a large daily herbage allowance (23·0 kg grass DM cow−1, measured above a height of 4·0 cm), supplemented with 0·5 kg d−1 of a ‘high‐magnesium’ concentrate. During the winter, animals on system HC were offered a silage of medium feeding value, mixed with ≈14·0 kg of concentrate d−1 (crude protein content of 202 g kg−1 DM) in the form of a complete diet. These animals commenced grazing on 9 April, achieving 24‐h turnout on 18 April. From 18 April until 9 June, daily herbage allowances and concentrate feed levels were 17·0 kg DM and 5·0 kg respectively; thereafter, and until day 305 of lactation, these daily allowances were reduced to 15·0 kg of herbage DM and 4·0 kg of concentrate. Animal performance during the first 305 days of lactation for systems HF and HC, respectively, were as follows: total concentrate DM inputs, 842 and 2456 kg; total silage DM intakes, 2205 and 1527 kg; total grass DM intakes, 3019 and 2044 kg; total feed DM intake, 6061 and 6032 kg and total milk output, 7854 and 8640 kg. Total milk output per cow with system HF was 786 kg lower than for system HC, despite similar total DM intakes, suggesting a greater total nutrient requirement with the former to support a given milk production. However, the study confirms that relatively similar levels of animal performance can be achieved from systems based on very different sources of nutrient supply.

Relationship of biomass yield of makhana (E. ferox) with soil properties and water quality

Simple and multiple relationships between biomass yield of makhana (E. ferox) and various soil and water properties have been investigated. The constituents, of the water phase were more closely related to the biomass yield than those in the solid phase. Most of the constituents in the water had more highly significant correlation coefficients with biomass yield than those of soil. The soil properties were either not related at all or only weakly related. Organic matter generally controlled the nutrition and physico-chemical behaviour of the soilwater system. These factors and the aquatic nature of the plant, indicated that mass flow was the main mechanism of nutrient uptake for this crop, for which organic matter decomposition was the main source of nutrient supply. The high value of the correlation coefficient of yield with ammonium, indicated the probability thatE. ferox can take up nitrogen in the ammonium form. Bicarbonate, pH and temperature were the other factors found to be closely related to biomass production. Micronutrients due to the reducing environment induced high availability and concentration in plants more than average and hence showed negative correlation.