Effects of Organic Amendments on Productivity and Profitability of Bell Pepper–French Bean–Garden Pea System and on Soil Properties during Transition to Organic Production

• Published in: Communications in Soil Science and Plant Analysis 2011-01, Vol.42 (21), p.2572-2585
• Main Authors: Gopinath, K.A, Saha, Supradip, Mina, B.L
• Format: Article
• Language: English
• Subjects: acid phosphatase; Agronomy. Soil science and plant productions; Azotobacter; Bell pepper; beta-glucosidase; Biological and medical sciences; bulk density; crop yield; economics; enzyme activity; french bean; Fundamental and applied biological sciences. Psychology; garden pea; General agronomy. Plant production; green beans; nutrient management; Organic farming; organic production; Other nutrients. Amendments. Solid and liquid wastes. Sludges and slurries; peas; phosphorus; Pisum sativum subsp. sativum var. sativum; poultry manure; Productivity; profitability; Pseudomonas putida; Rhizobium; Soil fertility; soil organic carbon; soil properties; Soil science; Soil sciences; Soil-plant relationships. Soil fertility; Soil-plant relationships. Soil fertility. Fertilization. Amendments; sweet peppers; transition
• ISSN: 0010-3624; 1532-2416; 1532-2416; 1532-4133
• DOI: 10.1080/00103624.2011.614033

A transition period of at least 2 years is required for annual crops before the produce may be certified as organically grown. There is a need to better understand the various management options for a smooth transition from conventional to organic production. The purpose of this study was to evaluate the effects of different organic amendments and biofertilizers (BFs) on productivity and profitability of a bell pepper-french bean-garden pea system as well as soil fertility and enzymatic activities during conversion to organic production. For this, the following six treatments were established in fixed plots: composted farmyard manure (FYMC, T1); vermicompost (VC, T2); poultry manure (PM, T3) along with biofertilizers (BF) [Rhizobium/Azotobacter + phosphorus solubilizing bacteria (Pseudomonas striata)]; mix of three amendments (FYMC + PM + VC + BF, T4); integrated nutrient management (FYMC + NPK, T5); and unamended control (T6). The yields of bell pepper and french bean under organic nutrient management were markedly lower (25.2-45.9% and 29.5-46.2%, respectively) than with the integrated nutrient management (INM). Among the organic treatments, T4 and T1 produced greater yields of both bell pepper (27.96 Mg ha-1) and french bean (3.87 Mg ha-1) compared with other treatments. In garden pea, however, T4 gave the greatest pod yield (7.27 Mg ha-1) and was significantly superior to other treatments except T5 and T1. The latter treatment resulted in the lowest soil bulk density (1.19 Mg m-3) compared with other treatments. Similarly, soil organic C was significantly greater in all the treatments (1.21-1.30%) except T2 compared to T6 (1.06%). Plots under INM, however, had greater levels of available nitrogen–phosphorus–potassium (NPK) than those under organic amendments. T1 plots showed greater dehydrogenase and acid phosphatase activities compared with other treatments. However, T4 and T5 plots had greater activities of beta-glucosidase and urease activities, respectively. The cost of cultivation was greater under organic nutrient management (except T2) compared with INM. The latter treatment gave greater gross margin and benefit/cost (B/C) ratio for all vegetables, except that T2 gave greater B/C ratio in garden pea compared with other treatments. We conclude that T1 and T4 were more suitable for enhancing the productivity of bell pepper-french bean-garden pea system, through improved soil properties, during transition to organic production.