Sains Malaysiana 52(4)(2023): 1069-1085

http://doi.org/10.17576/jsm-2023-5204-04

Influence of Beneficial Bacterial Inoculation on Nitrogen Concentration and Tomato Seedling Growth Under Glasshouse Conditions

(Pengaruh Inokulasi Bakteria Bermanfaat terhadap Kepekatan Nitrogen dan Pertumbuhan Anak Benih Tomato di bawah Keadaan Rumah Kaca)

AMAILY AKTER¹, ALI TAN KEE ZUAN^1*, SUSILAWATI BINTI KASIM¹, ADIBAH BINTI MOHD AMIN¹, ZAKRY FITRI BIN AB AZIZ², NOOR MD RAHMATULLAH³, MD EKHLASUR RAHMAN^1,4, BURAQ MUSA SADEQ¹ & SAYMA SERINE CHOMPA¹

¹Department of Land Management, Faculty of Agriculture, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia

²Faculty of Agriculture and Food Sciences, Universiti Putra Malaysia Bintulu Campus, Jalan Nyabau, 97008 Bintulu, Sarawak, Malaysia

³Department of Agricultural Statistics, Faculty of Agribusiness Management, Sher-e-Bangla Agricultural University, Dhaka-1207, Bangladesh

⁴Divisional Laboratory, Soil Resource Development Institute, Krishi Khamar Sarak, Farmgate, Dhaka-1215, Bangladesh

Diserahkan: 8 Ogos 2022/Diterima: 17 Februari 2023

Abstract

Many types of soil bacteria through antagonistic activity, thrive in the rhizosphere of plants or surround the tissues of plants and encourage plant development and reduce the nematode population. Bacteria as such are commonly known as Plant Growth-Promoting Rhizobacteria (PGPR). The purpose of this research was to determine Bacillus spp. inoculations impact on tomato seedling development with varying rates of chemical nitrogen-fertilizer. To minimize the recommended quantity of N fertilizer for tomato seedling development, a small pot experiment with selected PGPB was undertaken with varying amount of N fertilizer.  Plant growth-promoting bacteria (PGPB) labeled as UPMB10 and UPMRB9 (identified as Bacillus subtilis and Bacillus tequilensis, respectively) were utilized as microbial inoculants because they showed a significant improvement in seedling growth and N concentration in tomato plant tissues in a pot culture investigation. These microbial inoculants significantly improved the development of the plants, stem length, root length, leaves number, dry weight of shoots (stem, leaves), dry weight of roots, SPAD value, N concentration in tissues, and soil bacterial population. Bacteria-treated seedlings with 50% N fertilizer significantly increased stem length (69.07%), root length (78.51%), leaves number (68.58%), shoots (92.45%, 90.39%, stem and leaves, respectively), roots (73.33%), SPAD value (50.31%), and N concentration in plant tissues (63.79%) as compared to the uninoculated control. The findings also showed that inoculation of the Bacillus spp. tomato seedlings could save up to 50 percent of the recommended rate of chemical N fertilizer without affecting tomato seedling growth. The findings of this study suggest that the amount of nitrogen fertilizer given during tomato seedling development can be reduced by half, resulting in increased soil health and reduced environmental pollution.

Keywords: Inoculation; N levels; plant growth-promoting bacteria; tomato

Abstrak

Pelbagai jenis bakteria tanah melalui aktiviti antagonis, tumbuh subur dalam rizosfera tumbuhan atau mengelilingi tisu tumbuhan dan menggalakkan perkembangan tumbuhan dan mengurangkan populasi nematod. Bakteria seperti ini biasanya dikenali sebagai Rizobakteria Penggalak Pertumbuhan Tumbuhan (PGPR). Tujuan penyelidikan ini adalah untuk menentukan impak inokulasi Bacillus spp. kepada perkembangan anak benih tomato dengan kadar baja nitrogen kimia yang berbeza-beza. Untuk meminimumkan kuantiti baja N yang disyorkan untuk pembangunan anak benih tomato, satu uji kaji pasu kecil dengan PGPB terpilih telah dijalankan dengan jumlah baja N yang berbeza-beza. Bakteria penggalak pertumbuhan tumbuhan (PGPB) yang dilabelkan sebagai UPMB10 dan UPMRB9 (masing-masing dikenal pasti sebagai Bacillus subtilis dan Bacillus tequilensis) telah digunakan sebagai inokulan mikrob kerana ia menunjukkan peningkatan yang ketara dalam pertumbuhan anak benih dan kepekatan N dalam tisu tumbuhan tomato kajian kultur pasu. Inokulan mikrob ini dengan ketara meningkatkan perkembangan tumbuhan, panjang batang, panjang akar, bilangan daun, berat kering pucuk (batang, daun), berat kering akar, nilai SPAD, kepekatan N dalam tisu dan populasi bakteria tanah. Anak benih yang dirawat dengan 50% N bakteria baja dengan ketara meningkatkan panjang batang (69.07%), panjang akar (78.51%), bilangan daun (68.58%), pucuk (masing-masing 92.45%, 90.39% untuk batang dan daun), akar (73.33%), nilai SPAD (50.31%) dan kepekatan N dalam tisu tumbuhan (63.79%) berbanding kawalan tanpa inokulasi. Hasil kajian juga menunjukkan bahawa inokulasi Bacillus spp. anak benih tomato boleh menjimatkan sehingga 50 peratus daripada kadar baja N kimia yang disyorkan tanpa menjejaskan pertumbuhan anak benih tomato. Hasil kajian ini juga mencadangkan bahawa jumlah baja nitrogen yang diberikan semasa pembangunan anak benih tomato dapat dikurangkan sebanyak separuh, menyebabkan kesihatan tanah meningkat dan pencemaran alam sekitar berkurangan.

Kata kunci: Bakteria penggalak pertumbuhan tumbuhan; inokulasi; tahap N; tomato

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