The application of ammonium sulphate and amino acid on cotton: effects on can improve growth, yield, quality and nitrogen absorption

A field study was carried out to determine the influence of foliage applied plant growth promoter and retardant in improving soil applied sulphur fertilizer use efficiency in cotton during two consecutive summers 2014 and 2015. Experimental trial comprised of three different sources of sulphur (ammonium sulphate, potassium sulphate and elemental sulphur) and foliar spray of plant growth promoter and growth retardant including tap water was taken as control. Among treatments soil applied ammonium sulphate with foliage applied amino acid produced maximum plant height, sympodial branches, pods per plant, seed cotton yield, fiber yield, biological yield, protein contents, oil contents and leaf nitrogen uptake as compared to the other treatments. Whereas, soil applied potassium sulphate with foliar spray of mepiquat chloride on cotton significantly improved the boll weight and leaf potassium uptake. We conclude that soil applied ammonium sulphate and foliage spray of amino acid was more effective in improving the productivity and quality attributes of cotton.

In vitro plant growth promoter assay of actinobacteria potential for tidal land farming

The use of tidal land for agricultural still faces constraints, mainly due to high iron content. Actinobacteria produce bioactive compound with many functions. The aim of this work was to assess the growth of actinobacteria at various iron concentrations and its capability as plant growth promoter. Four actinobacteria isolates (Cal31t, Dbi28t, Crc32t and Cal24h) were grown at various iron concentrations. The isolates were examined for their capability to produce IAA and fix N2 under in vitro assay. The growth of actinobacteria under stress conditions was examined by cultivating them in ISP2 medium at pH 4, 3% NaCl, 750 mg.L−1 AlCl3 and 8 concentrations of FeCl3, i.e. 0, 500, 1000, 2000, 4000, 8000, 16000, 32000 mg.L−1. Actinobacteria isolates were able to grow under iron stress condition up to 32.000 mg.L−1. Both Cal3t and Dbi28t produced higher cell biomass compared with the other two tested isolates. All isolates produced IAA when grown under iron stress condition up to 4000 mg.L−1 of FeCl3, were able to grow under N-free medium and capable to produce ammonia at various concentrations. Crc32t produced the highest number of ammonia (0,354 mg.L−1). Cal31t and Crc32t isolates have the potency as plant growth promoter in tidal land farming.

Rhizosphere Streptomyces formulas as the biological control agent of phytopathogenic fungi Fusarium oxysporum and plant growth promoter of soybean

Sari M, Nawangsih AA, Wahyudi AT. 2021. Rhizosphere Streptomyces formulas as the biological control agent of phytopathogenic fungi Fusarium oxysporum and plant growth promoter of soybean. Biodiversitas 22: 3015-3023. Rhizosphere Streptomyces are considered as promising sources of plant growth-promoting rhizobacteria (PGPR) and biocontrol agents against pathogenic fungi, particularly Fusarium oxysporum causing root rot, cotyledon rot, hypocotyl rot, and stunted growth in soybean. Formulation of rhizosphere Streptomyces with appropriate carrier materials is necessary to facilitate storage and application in plants. This study aimed to develop a formulation of rhizosphere Streptomyces, apply the formula to control F. oxysporum, and promote soybean plant growth. Five Streptomyces isolates, i.e., Streptomyces panaciradicis ARK 13, Streptomyces tritolerans ARK 17, Streptomyces recifensis ARK 63, Streptomyces tendae ARK 91, and Streptomyces manipurensis ARK 94 were used in this study. All of the isolates could grow in potato broth, rice bran extract, and molasses as alternative media. The highest biomass produced from the molasses growth medium. All five isolates had antifungal activity against F. oxysporum with the inhibition percentage ranging from 41% to 76%, and all of them were detected to have the iaaM gene. Indole-3-acetic acid (IAA) hormone produced by these isolates were ranging from 8.99-15.14 mg L-1, with the phosphate solubilization index of 2.13-2.47. Five rhizosphere Streptomyces formulas with the main carrier of peat could maintain the viability with the population density of 108 CFU g-1 for 8 weeks of storage at room temperature. Two formulas, F17 and F94, were the best formulas to control disease caused by F. oxysporum with disease suppression of 74% in sterile soil and 80-85% in non-sterile soil. Formula F17 and F94 significantly increased soybean growth in sterile and non-sterile soils. Therefore, these formulas could be recommended as biocontrol and plant growth promoters of soybean.