Search

A long-term experiment was conducted at the Central Research Institute for Dryland Agriculture for 13 years to evaluate the effect of low tillage cum cheaper conjunctive nutrient management practices in terms of productivity, soil fertility, and nitrogen chemical pools of soil under sorghum–mung bean system in Alfisol soils. The results of the study clearly revealed that sorghum and mung bean grain yield as influenced by low tillage and conjunctive nutrient management practices varied from 764 to 1792 and 603 to 1008 kg ha−1with an average yield of 1458 and 805 kg ha−1over a period of 13 years, respectively. Of the tillage practices, conventional tillage (CT) maintained 11.0% higher yields (1534 kg ha−1) over the minimum tillage (MT) (1382 kg ha−1) practice. Among the conjunctive nutrient management treatments, the application of 2 t Gliricidia loppings + 20 kg nitrogen (N) through urea to sorghum crop recorded significantly highest grain yield of 1712 kg ha−1followed by application of 4 t compost + 20 kg N through urea (1650 kg ha−1) as well as 40 kg N through urea alone (1594 kg ha−1). Similar to sorghum, in case of mung bean also, CT exhibited a significant influence on mung bean grain yields (888 kg ha−1) which was 6.7% higher compared to MT (832 kg ha−1). Among all the conjunctive nutrient management treatments, 2 t compost + 10 kg N through urea and 2 t compost + 1 t Gliricidia loppings performed significantly well and recorded similar mung bean grain yields of 960 kg ha−1followed by 1 t Gliricidia loppings + 10 kg N through urea (930 kg ha−1). The soil nitrogen chemical fractions (SNCFs) were also found to be significantly influenced by tillage and conjunctive nutrient management treatments. Further, a significant correlation of SNCF with total soil nitrogen was observed. In the correlation study, it was also observed that N fraction dynamically played an important role in enhancing the availability pool of N in soil and significantly influenced the yield of sorghum grain and mung bean. [ABSTRACT FROM AUTHOR]

Field experiments were conducted in farmyard manure (FYM) and maize-residue (MR) blocks during 1984–2011 with the objective of identifying a superior treatment for attaining maximum finger millet yield and soil fertility at Bangalore. The treatments tested in the FYM block were Control; FYM@10tha−1; FYM@10tha−1 + 50% nitrogen, phosphorus, and potassium (NPK); FYM@10tha−1 + 100%NPK; 100%NPK; and in the MR block, Control; MR@5tha−1; MR@5t ha−1 + 50%NPK; MR@5tha−1 + 100%NPK; 100%NPK. FYM@10t/ha + 100%NPK gave a maximum mean yield of 3207 kg/ha in the FYM block, while MR@5t/ha + 100%NPK gave 2548 kg/ha in the MR block. Regression and principal component (PC) models of yield were developed through soil fertility and rainfall variables to assess the treatments. Maximum yield predictability of 60% and 65% under regression, and 76% and 75% under the PC model were observed for the FYM and MR blocks, respectively. FYM@10t/ha + 50%NPK was superior, with maximum gross returns of Rs.41286/ha and benefit–cost ratio (BCR) of 2.27 in the FYM block compared to MR@5t/ha + 100%NPK (gross returns of Rs.34530/ha and BCR of 2.09) in the MR block with maximum soil fertility, and are recommended for adoption under semi-arid Alfisols. [ABSTRACT FROM AUTHOR]

Vertisol soils of central India are heavy in texture, with high clay content and low organic matter. These soils are prone to degradation and the soil loss is due to poor management practices including excessive tillage. Based on a long-term study conducted for improving the quality of these soils, it was found that management practice such as low tillage (LT) + 4 t ha−1compost + herbicide (Hb) recorded significantly higher organic carbon (OC) (6.22 g kg−1) and available N (188.5 kg ha−1) compared to conventional tillage (CT) + recommended fertilizer (RF) + off-season tillage (OT) + hand weeding (HW) (OC: 4.71 g kg−1, available nitrogen (N) (159.3 kg ha−1). Among the physical soil quality parameters, mean weight diameter (MWD) was significantly higher under LT + 4 t ha−1straw + Hb (0.59 mm). The practice of LT + 4 t ha−1straw + HW recorded significantly higher microbial biomass carbon (MBC) (388.8 μg g−1). The order of key indicators and their contribution towards soil quality was as follows: OC (29%) >, MBC (27%) > available zinc (Zn) (22%) > MWD (9%) > available boron (B) (8%), > dehydrogenase activity (DHA) (5%). The order of the best treatment which maintained soil quality index (SQI) values reasonably good (>1.5) was as follows: LT + 4t ha−1compost + HW (1.65) > LT + 4 t ha−1compost +Hb (1.60) > LT + 4t ha−1straw + HW (1.50). Hence, these treatments could be recommended to the farmers for maintaining higher soil quality in Vertisols under soybean system. Correlation studies revealed stronger relationship between key indicators like OC (R2 = 0.627), MBC (R2 = 0.884), available Zn (R2 = 0.739) and DHA (R2 = 0.604) with Relative Soil Quality Index (RSQI). The results of the present study would be highly useful to the researchers, farmers and land managers. [ABSTRACT FROM AUTHOR]

A long-term experiment was conducted to evaluate the effect of integrated use of organic and inorganic sources of nutrients on soil quality and its relation to finger millet yield under two predominant crop rotations viz., groundnut–finger millet and finger millet monocropping in hot moist semiarid rainfed Alfisol soils in South India. Two experiments were laid out separately for each cropping system in a randomized complete block design with five treatments individually with FYM and maize residue-based combinations viz., Control (T1), FYM @ 10t ha−1or Maize residue (MR) @ 5t ha−1(T2), farm yard manure (FYM) @ 10t ha−1or Maize residue (MR) @ 5t ha−1 + 50% RDF (Recommended Fertiliser Dose) N, P2O5& K2O (T3), FYM @ 10t ha−1or Maize residue (MR) @ 5t ha−1 + 100% RDF N,P2O5& K2O (T4), Recommended N, P2O5& K2O (T5). Thus, four sets of nutrient management systems were evaluated. The results showed that farm yard manure or maize residue application in combination with recommended dose of fertilizer significantly improved the soil physical, chemical, and biological properties compared to control and application of inorganic fertilizers alone. Based on evaluation of 19 soil quality parameters under each of the four nutrient management systems, the common key soil quality indicators emerged out were: organic C (OC), available nitrogen (N), available sulfur (S), and mean weight diameter (MWD) of soil aggregates. A significant correlation between the finger millet yield and the relative soil quality indices (RSQI) indicates the importance of soil quality in these semiarid Alfisol soils. The results and the methodology adopted in the present study could be of importance in improving the soil quality not only for the region of the study, but also in other identical soils and cropping systems across the world. [ABSTRACT FROM AUTHOR]

Soil-test crop-response experiments on rice were conducted in the Bastar Plateau Agroclimatic Zone of Chhattisgarh during 2009–2011 to assess yield, soil, plant, and fertilizer nitrogen (N), phosphorus (P), and potassium (K) nutrient relationships and calibrate optimum fertilizer doses for attaining yield targets. Soil fertility status was poor to medium for N (194–283 kg ha−1) and P (7.53–19.66 kg ha−1), and medium to good for K (226–320 kg ha−1). Based on nutrient requirements (NR, kg q−1) and contributions from soil (CS, %), fertilizer (CF, %), and farmyard manure (CFYM, %), optimum fertilizer doses were derived. The fertilizer doses were validated for attaining yield targets of 5000 and 6000 kg ha−1in farmer’s fields. Rice yield within 10% deviation was attained, which indicated that soil-test-based fertilizer dose was superior. This approach could be adopted for regions with similar soil and agroclimatic conditions in other parts of the world to increase rice yields. [ABSTRACT FROM PUBLISHER]

Inceptisols in the submountainous region of Indo-Gangetic Plains in India are known as low productive areas due to several constraints like decline in soil organic matter and fertility, deterioration of soil physical and biological properties. The present study was conducted with tillage as main treatments and integrated nutrient management as subtreatments to improve soil quality and to identify the key indicators of soil quality after 5 years of experimentation in maize–wheat cropping system at Ballowal Saunkhri. Conventional tillage (CT) + interculture (IC) maintained significantly higher soil quality indices (SQI) of 1.12 which was at par with 50% CT + IC + chemical weed control (CWC) (1.08). Application of nitrogen (N) through 50% (organic) + 50% (inorganic) maintained higher soil quality with SQI of 1.10 followed by application of 100% N through organics (1.08). The results indicated that reduction in the intensity of tillage to 50% with interculture practices and combined use of organic and inorganic fertilizers maintained higher soil quality in these degraded Inceptisols. The methods of principal component analysis and computation of SQI adopted will be highly useful to future researchers, land managers, and students at locations across the world having similar climatic and edaphic conditions. [ABSTRACT FROM AUTHOR]

To identify the best combinations of micronutrient-based fertilization treatments in terms of crop yield and nutrient uptake, three field experiments with greengram−fingermillet as the test sequence with 12 treatments on micronutrient-based fertilization [with recommended nitrogen (N)−phosphorus (P)−potassium (K) fertilizer] were conducted during 2005 to 2007 in a semi-arid Alfisol at Bangalore. The effects of treatments on available soil and plant uptake of nutrients [N, P, K, sulfur (S), iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), boron (B), and molybdenum (Mo)] and yield of crops were assessed based on standard analysis of variance procedure. Using the relationships of yield with soil and plant nutrient variables, regression models of yield through soil and plant variables were calibrated and effects of variables on crop yields were assessed. The models gave high and significant yield predictability in the range of 0.87 to 0.98 through different variables. The model of plant uptake through soil nutrients indicated that soil S, Fe, and Zn had significant positive effects, whereas soil N, K, B, and Mo had negative effects on plant nutrient status in greengram. Similarly, soil P, Mn, and Zn had significant positive effects, whereas soil N, K, and Fe had negative effects on plant uptake of nutrients in fingermillet. Based on a relative efficiency index (REI) criteria, T2 for plant uptake and T12 for maintaining soil nutrients were found to be superior in greengram, whereas T2 for plant uptake and T8 for maintaining soil nutrients were found to be superior in fingermillet over years based on REI. The combined REI over soil and plant nutrients for both crops indicated that application of T8 for greengram and T2 for fingermillet could be prescribed for attaining maximum plant uptake of nutrients and productivity of crops in sequence, apart from maintaining maximum soil fertility of nutrients under semi-arid Alfisols. [ABSTRACT FROM PUBLISHER]

A large number of seeds exhibiting intermediate and recalcitrant storage physiology, generally found in the tropics, subtropics, aquatic, and riparian environments, pose difficulty in ex-situ conservation because of their inherent intolerance to desiccation. The rapid drying of such seeds, especially intermediate seeds, renders them tolerant to desiccation to sufficiently low moisture content suitable for ex-situ conservation. The aim of this work was to establish the seed-storage physiology of Dipcadi saxorum, an endangered plant species of India, and develop suitable ex-situ storage protocol for conservation. Ex-situ storage potential of short-lived (4 months) seeds of D. saxorum was extended to 18 months by storage at 15°C after rapid drying of freshly harvested seeds to low (4%) moisture content (MC). Seeds exhibited 99-100% viability during storage under ambient conditions (slow-drying) up to 50 d (8.9% MC) but storage for 70 d resulted in 78% germination (6.5% MC). Seeds became nonviable after 170 d of storage (registering 5.1% MC) under ambient conditions. In contrast, the rapid-drying using silica gel reduced the MC from 42.42 to 4.5% within 9 h and showed 100% germination. The storage potential of rapidly dried (4, 9, 15 and 30% MC) seeds (tested at 25, 15, and -20°) increased to 18 months; seeds rapidly dried to 4% MC at 15°C gave 25% germination. Electrolyte leakage loss was reduced in the rapidly dried seeds compared with slow-dried seeds and negatively correlated (ranging from R2 = -0.97 to -0.99) with the percentage germination. Compared with slow drying, the rapid drying of seeds to 4 and 9% MC improved significantly the storage potential of D. saxorum seeds at all the storage temperatures studied. Our study revealed that seeds of D. saxorum exhibited intermediate storage physiology and can be desiccated to sufficiently low moisture content (4%) well suited for ex-situ storage for conservation, if rapidly dried despite their sensitivity to desiccation. [ABSTRACT FROM AUTHOR]

Suitability of the electro‐ultrafiltration (EUF)‐potassium (K) quotient, a ratio between strongly held and easily desorbable EUF fractions of K to measure K‐buffering capacity of illite‐dominant soils under intensive cropping, was studied. EUF‐K quotients which ranged from 0.333 to 0.580 before cropping increased to the range of 0.405 to 0.710 after the cropping. As a result of cropping, the mean K‐ replenishment rate decreased from 6.98 kg/ha/day to 0.2 kg/ha/day, whereas the mean EUF‐K quotient increased from 0.43 to 0.53. EUF‐K quotient showed significant positive correlation with dry matter yield (r = 0.78*) and K uptake (r = 0.79*) in the first harvest of crop and in the subsequent harvests it maintained correlations of lower order. While other EUK‐K fractions, i.e. EUF 20°C, EUF 80°C, and EUF 35 min increased or maintained the same extent of correlation with conventional soil test methods after cropping, EUF‐K quotient failed to have significant correlation with those soil test methods after cropping. The current study brought out that exhaustive cropping differentially depleted the EUF fractions leading to an increase in the estimated buffering capacity (EUF‐Q) which failed to show satisfactory relationship with K removal by the crop. [ABSTRACT FROM PUBLISHER]