Influence of Trichoderma harzianum and Bacillus thuringiensis with reducing rates of NPK on growth, physiology, and fruit quality of Citrus aurantifolia

Abstract

Continuous use of chemical fertilizers gradually shrinks the crop yield and quality, and these adverse effects can be reduced by adopting new sustainable practices such as the use of manure, biofertilizers, and nano fertilizers. Limited information is existed on the application of Trichoderma harzianum and Bacillus thuringiensis microbes to improve lemon seedlings growth, physiology, and fruit formation. Therefore, the current study is aimed to evaluate the effects of T. harzianum and B. thuringiensis microbes mixing with low levels of inorganic fertilizer (NPK) on the plant growth, development, and quality of limau nipis (key lemon) fruits. The lemon seedlings growing media were inoculated during transplanting with T. harzianum and B. thuringiensis at various NPK fertilizers under polybagged conditions. The seedlings were grown around eighteen (18) months after inoculation with biofertilizers followed by Randomized Complete Block Design (RCBD) with five (5) replications. The results showed that T. harzianum with 50 g of NPK treatment (T2) increased the seedling's height, branch number, leaf height, ground area, and absolute growth rate (AGR) plant height by 50.12%, 107.84%, 17.91%, 17.91%, 116.93%, and 56.02%, respectively, over the control treatment. The number of leaves (60.82%), leaf area (42.75%), stem diameter (27.34%), specific leaf area (SLA) (39.07%), leaf area index (LAI) (54.40%), and absolute growth rate for leaf number (73.86%), leaf area (306.85%) and stem diameter (46.8%) of lemon seedlings increased significantly with B. thuringiensis plus 50 g NPK treatment (T3). The applications of B. thuringiensis with 25 g NPK fertilizer treatment (T5) increased leaf fresh weight (LFW), leaf dry weight (LDW), leaf moisture content (LMC), specific leaf weight (SLW), leaf relative growth rate (RGR), and chlorophyll content by 96.45%, 56.78%, 13.60%, 24.76%, 45.45%, and 16.22%, respectively, over the control group. In addition, T5 treatment increased the fruits number, individual fruit weight, fruit diameter, fruit dimension, leaf total soluble solids (TSS), and fruit TSS content of lemon tress by 81.81%, 55.52%, 43.54%, 25.69%, 89.47%, and 70.78% compared to the control treatment. Furthermore, soil inoculation of B. thuringiensis significantly increased the pulp to peel ratio and juice content of lemon fruits. From this study, it can be concluded that soil inoculation of both T. harzianum and B. thuringiensis with 25-50% NPK during transplanting improved plant growth, physiology, and fruit quality of limau nipis trees.

Application of Trichoderma harzianum and Bacillus thuringiensis in increasing plant growth of Aceh patchouli (Pogostemon cablin Benth)

“…Plant canopy (crown) is also influenced by height, and plant branching, the higher the plant and plant branching will be directly proportional to the width of the plant crown in chili [15]. The application of T. harzianum and B. thuringiensis can increase the number of leaves and crowns of Patchouli leaves compared to the control treatment [16], increasing plant size because the application of Trichoderma sp. can increase the C-organic content in the soil and ultimately improve crop quality [17].…”

Effects of Land Preparation Method and Organic Soil Amendment on Soil Properties, Growth and Yield of Maize (Zea mays)

“…2.5 t BSF also increased maize stem diameter by 9% and 18% in S1 and S2 respectively. Studies have shown that application of Trichoderma led to an increase in stem diameter by 23%, 42% and 27.3% respectively [25,69,70).…”

Effect of Trichoderma asperelloides (TA41) on Production and Quality of Strawberry (Fragaria ananassa) c.v. Winter Dawn

“…The maximum Increase in fruit weight following use of Trichoderma asperelloides might be due to its effect in cell division and cell elongation. Trichoderma asperelloides is also reported to promote growth by increasing plasticity of cell wall followed by hydrolysis of starch into sugar which reduces cell wall potential, resulting in the entry of water into the cell and causing its elongation Abdelmoaty et al [15]…”