Soil salinity is one of the major obstacles that is limiting the growth and yield of groundnut. This study aims to investigate the effect of growth-promoting fungi, Trichoderma, on groundnut plants that were cultivated in saline conditions. Five different Trichoderma isolates were grown in four different NaCl concentrations. Selected Trichoderma were then applied to the groundnut seeds and their growth and development were monitored during the study. Growth inhibition, volatile organic compounds, chlorophylls, carotenoids, total phenolics and flavonoids, and minerals were assessed between the Trichoderma treatments. Increasing the salt concentration from 0.25–0.75 M decreased the growth of the Trichoderma isolates. The amounts and profiles of the volatile organic compounds from the T. asperellum isolate were significantly different to those in the T. virens isolate. In the vegetative growth stage, increased chlorophyll content was recorded in both the T. asperellum and T. virens-treated groundnut. The leaves that were obtained from the groundnut that was treated with T. virens T.v4 contained significantly higher indole-3-acetic acid (420 µg IAA/g) than the same plants’ roots (113.3 µg IAA/g). Compared to the control groundnut, the T. asperellum T.a8-treated groundnut showed increased phenolics (31%) and flavonoids (43%) and increased shoots and biomass weight at the generative growth stage. This study demonstrates that Trichoderma, with their plant growth promotion ability, could potentially be used to improve the growth of groundnut growing under salinity stress. Importantly, salt-tolerant Trichoderma could be regarded as a beneficial and sustainable way to improve the survival of salt-sensitive crops.

Inayati A, Sulistyowati L, Aini LQ, Yusnawan E. 2020. Trichoderma virens-Tv4 enhances growth promoter and plant defense-related enzymes of mungbean (Vigna radiata) against soil-borne pathogen Rhizoctonia solani. Biodiversitas 21: 2410-2419. Trichoderma virens has been studied for its ability to control various soil-borne pathogens as well as to induce plant resistance. The ability of T. virens control R. solani and its capability to induce resistance was evaluated in two different genotypes of mungbean (Vigna radiata (L.) R. Wilczek). Plant growth-promoting capability and production of plant defense-related enzymes during plant-pathogen-Trichoderma interaction were investigated. Pathogen infection caused the morphological and biochemical changes as well as increased plant defense enzymes activity such as peroxidase, polyphenol oxidase, PAL, phenolics, and flavonoid compared to control uninoculated plants. T. virens improved mungbean seedling growth in terms of increased total biomass, root weight, and root length as well as improved chlorophyll content and IAA-synthase from leaves and roots. T. virens treatment alone or in the presence of pathogen-induced mungbean defense-related enzymes indicated by the increasing of PO and PPO activity, and higher accumulation of total phenolic and flavonoid content. Although most of plant induced resistance parameters showed low and non-significant in direct single-factor comparison, Pearson’s correlation showed there was a positive correlation between plant growth promoter compounds (IAA and chlorophyll) with plant defense-related enzymes (total phenol, and flavonoid content). T. virens treatment can induce systemic defense response of mungbean seedling directly by increasing the activity of some defense-related enzymes, and indirectly by improving plant health, and promoting plant growth. In conclusion, T. virens-Tv4 has potential to be developed as bio-control agents to control R. solani as well as to induce mungbean resistance.

Kedelai merupakan komoditas aneka kacang nomor satu di Indonesia. Kedelai digunakan sebagai bahan baku pembuatan tempe dan susu kedelai. Kandungan protein yang tinggi dan cita rasa yang enak pada olahan tempe menyebabkan komoditas ini, masih menjadi bahan baku utama. Produktifitas kedelai dapat terhambat oleh pengaruh faktor biotik, seperti serangan jamur patogen. Phakopsora pachyrhizi merupakan patogen penting pada tanaman kedelai dan menyebabkan penyakit karat. Infeksi patogen ini menyebabkan tanaman menguning dan menua dini, sehingga berpengaruh terhadap pembentukan polong dan biji. Penelitian ini menggunakan lima puluh varietas kedelai untuk melihat respon ketahanan varietas terhadap infeksi patogen. Infeksi dilakukan secara alami di lahan endemik penyakit karat pada awal musim kemarau. Pengamatan terdiri dari gejala, skroring serangan dan penentuan kriteria ketahanan menggunakan metode IWGSR. Hasil penelitian menunjukkan bahwa terdapat dua puluh tujuh varietas yang memiliki tipe ketahanan rentan, dua varietas menunjukkan respon agak rentan, sembilan varietas menunjukkan respon agak tahan, dan dua belas varietas menunjukkan respon tahan. Varietas yang menunjukkan respon tahan adalah varietas kawi, mutiara 3, wilis, gepak kuning, dena 2, menyapa, detam 2, merbabu, argopuro, slamet dan pangorango. Informasi ini dapat menjadi salah satu pertimbangan dalam pemilihan tetua untuk perakitan varietas kedelai yang tahan penyakit karat daun.

The productivity of cassava in acid dryland is generally still low. Fertilization, land amelioration, and superior varieties are the main solutions for increasing cassava productivity. This research aimed to determine the response of high-yielding varieties and fertilization technology packages to the growth and yield of cassava in acid dryland of Sukaharja Village, Warung Kiara District, Sukabumi Regency, West Java. The contents of organic carbon, nitrogen, and magnesium of the soil is below the minimum threshold, so the application of N fertilizer, organic matter, and ameliorant is expected to increase plant growth. The research consisted of two treatment factors: two cassava varieties and three fertilization technologies. The treatments were arranged in a completely randomized split-plot experimental design with three replications with variety as the main plot and fertilization technology package as the subplots. The treatment effect was observed on the character of plant height, wet biomass weight, stem diameter, number of tubers, tuber length, tuber diameter, tuber weight (large and small) per plant, and tuber yield per plot to be converted per ha. Tuber quality was observed by observing water content, percent dry matter, and starch yield. The results showed that the fertilization technology package increased plant height, fresh biomass weight, stem diameter, large tuber weight per plant, and yield per hectare in both varieties. Differences in varieties and fertilization technology packages have no effect on starch levels.