ABSTRACT
Field experiments were conducted at Agricultural College Farm, Bapatla during Kharif and Rabi seasons of 2017-2018 and 2018-2019 to study the Phosphorus dynamics in relation to nutrient management in rice- blackgram cropping sequence with respect to changes in soil nutrient status. Results of two years (2017-2019) experimentation revealed that at all growth stages of rice, significantly highest available nitrogen, phosphorus and potassium in soil were recorded with application of RDNK+Dhaincha @ 10t ha-1 (M3) and this was on par with RDNK+ Sunhemp @ 10t ha-1(M2), whereas lowest was recorded in RDNK (M0) alone in both seasons of study. Among the P levels the available nutrient status (N, P and K) were increased with the increasing level of P from 0 (P1) to 120 kg P2O5 (P5) ha-1, irrespective of the nutrients imposed to rice crop. Significantly highest was recorded in P5 (120 kg P2O5 ha-1) and this was on par with P4 (90 kg P2O5 ha-1), whereas the lowest was recorded in treatment P1 that received 0 kg P2O5 ha-1.
ABSTRACT
Objective: To study the effect model of various fertilization combinations of nitrogen (N), phosphorus (P), and potassium (K) and its effects on the yield of flowers of Chrysanthemum indicum (FCI) and linarin content. Methods: The "3414" mis-classification orthogonal design was used in the fertilization test of three factors (N, P, and K), quadratic regression design was adopted, and analyses on variance and the DPS were carried out by using C. indicum as material. Results: After statistical analysis, the optimized effect model of N, P, and K and the the relationship between the yield and quality of FCI were established. The optimum efficiency was the treatment with N2P2K2 in various fertilizations. No treatment or single treatment of N, P, or K could cause the reduction of yield and quality. Single-factor analysis showed that the yield and linarin content were first increased and then decreased steadily with the increase of the N, P, and K application. The two factor interaction analysis indicated that there existed an interaction range among N, P, and K with the yield as the index. Synergistic effect was observed while the amount of N, P, and K was lower than the range while antagonistic effect was observed while higher than the range. When taking the content of linarin as the index, the reaction between N-K and P-K existed a range, and the trend of linarin showed the same trend as the yield. While N-P always kept the synergistic effect. Conclusion: The optimal fertilization amounts in the optimized model of FCI are 131.280-187.254 kg/hm2 for N, 113.415-170.460 kg/hm2 for P, 118.335-220.845 kg/hm2 for K, respectively.
ABSTRACT
This study evaluated the effects of inoculation with the arbuscular mycorrhizal fungi Glomus mosseae, Glomus intraradices A4 and Glomus intraradices B1 and two phosphorus levels (10 and 40 mg kg-1) on root colonization, plant growth, nutrient uptake and essential oil content in Mentha piperita L. The experiment was carried out in a greenhouse, in 4x2 factorial arrangement, in completely randomized design. At sixty days after transplanting, the mycorrhizal plants had significantly higher fresh matter, dry matter and leaf area compared to non-mycorrhizal plants. The inoculation increased P, K and Ca levels in the shoot which were higher under 40 mg P kg-1 of soil. Plants grown with 40 mg P kg-1 soil increased the essential oil yield per plant by about 40-50% compared to those cultivated with 10 mg P kg-1, regardless of the mycorrhizal treatment. Among the studied fungal species, inoculation with G. intraradices A4 and a high level of P significantly increased plant growth and essential oil yield, compared to the other studied mycorrhizal fungal species. In conclusion, inoculation of arbuscular mycorrhizal fungi into peppermint plants is a feasible alternative to increase the essential oil production and reduce the use of fertilizers required to obtain economic production of peppermint under phosphorus-deficient soil condition.
Este estudo avaliou os efeitos da inoculação de fungos micorrízicos arbusculares Glomus mosseae, Glomus intraradices A4 e Glomus intraradices B1 e duas doses de fósforo (10 e 40 mg kg-1) sobre a colonização radicular, crescimento, absorção de nutrientes e óleos essenciais em Mentha piperita L. O estudo foi conduzido em casa de vegetação no delineamento inteiramente casualizado em esquema fatorial 4x2. Sessenta dias após o transplantio, as plantas micorrizadas apresentaram massa fresca, massa seca, e área foliar significativamente maior em comparação as não-micorrizadas. A inoculação aumentou o teor de P, K e Ca na parte aérea sendo superiores em 40 mg P kg-1 de solo. As plantas cultivadas com 40 mg P kg-1 de solo aumentaram a produção de óleo essencial por planta cerca de 40-50% em relação às cultivadas com 10 mg de P kg-1, independentemente da micorrização. Dentre as espécies fúngicas estudadas, a inoculação com G. Intraradices A4 e com um elevado nível de P, aumentou significativamente o crescimento e rendimento de óleos essenciais em comparação com outras espécies de fungos micorrízicos estudados. Em conclusão, a inoculação dos fungos micorrízicos arbusculares em plantas de hortelã é uma alternativa viável para aumentar a produção de óleos essenciais e reduzir o uso de fertilizantes necessários para a produção econômica de hortelã-pimenta com deficiência de fósforo no solo.