Cekaman kekeringan menyebabkan terjadinya perubahan terhadap pertumbuhan dan produksi tanaman diantaranya terjadinya penurunan laju asimilasi. Percobaan dilaksanakan di Rumah Plastik Lapangan Riset Padi Babakan, University Farm IPB, Bogor (± 240 m dpl) pada bulan September 2011 sampai February 2012. Rancangan penelitian menggunakan rancangan split plot 3 ulangan, dengan dua faktor perlakuan yaitu faktor utama (Cekaman kekeringan) sebagai petak utama yang terdiri dari penghentian pemberian air umur 3Minggu Setelah Transplanting (3MST) sampai panen; Penghentian pemberian air umur  6 MST sampai panen; penghentian pemberian air umur 9 MST sampai panen dan  kontrol.  Sedangkan faktor kedua adalah varietas yang ditempatkan sebagai anak petak yaitu IR 64, Ciherang, IPB 3S, Way Apo Buru, Jatiluhur, Menthik Wangi, Silugonggo dan Rokan. Hasil penelitian menunjukkan perlakuan cekaman kekeringan pada saat awal fase vegetatif sampai panen dan pada fase pra antesis sampai panen menyebabkan terjadinya penurunan laju asimilasi bersih berkisar 42.96%-78.95% dan laju tumbuh relatif berkisar 22.95%-69.62%. Varietas Jatiluhur dan Ciherang memiliki laju asimilasi bersih yang lebih tinggi pada perlakuan cekaman kekeringan yang diberikan pada awal fase vegetatif sampai panen

The efforts of the rooting of regenerants resulting from gamma-ray irradiation require plant tissue culture, which known as micrografting. This technique can help irradiated regenerants to develop a well root system, by combining non-rooting shoots with rooted in vitro cultured shoots of plant rootstock. The purpose of this study was to examine the effect of seed explants cutting and the application of different BAP concentrations for the successful micro-grafting of mangosteen in vitro. This experiment employed Complete Randomized Design (CRD) Factorial with two factors and ten replications. The first factor was the cutting treatments of mangosteen seeds explants for rootstock shoots, consisting of 2 types of seeds: uncut and cut seeds. The second factor was BAP concentrations: BAP 0 mg/l and BAP 2 mg/l. The results showed that the division of the seeds had an influence on the results of micro-grafting mangosteen in vitro. Micrografted mangosteen, which rootstock applied from undivided seeds, possessed faster growth, longer shoots, and produce more leaves compared to rootstock shoots from the divided seeds. BAP concentrations also contributed to the results. The application of BAP 2 mg/ demonstrated better effect on all variables observed. There were no interactions between seed divisions and BAP concentrations in all observed variables.

Rice is the main staple food for Indonesian people where it is cultivated in the paddy field. Considering the population growth in Indonesia is increasing, it requires an effort to increase rice production to meet the needs of the growing population. One of the efforts is through planting superior varieties such as IPB 3S with a planting system which is known as “Jajar Legowo”. This research was conducted from January to April 2018 in Puloe Iboih Village, Kuta Makmur Sub-district, North Aceh and Agroecotechnology Laboratory, Malikussaleh University. The purpose of this research is to discover the impact of the “Jajar Legowo” planting system on the growth and production of IPB 3S variety. This research used  Randomized Block Design (RBD) Non-Factorial with planting system Jajar Legowo (3:1 and 4:1) which have plant spacing 25cmx25 cm with space between plants 40 cm. These treatments had 3 replications. The results revealed that planting system Jajar Legowo significantly increased the number of tillers at 50 and 60 days after planting, plant height at 30 days after planting, the amount of chlorophyll at 60 days after planting, grain weight, yield, and harvest index. From this research, it is found that the best plant spacing in the Jajar Legowo planting system was 3:1.

The application of modern biotechnology is needed in order to enhance the genetic diversity of mangosteens. The application of tissue culture on mangosteens is an important thing to do to support the biotechnology program of mangosteen plants. The purpose of this research is to reveal the influence of location of explants and Benzylaminopurine (BAP) concentration on germination of local Acehnese mangosteens in vitro. This research was conducted at the Laboratory of tissue culture of the Faculty of Agriculture, Malikussaleh University from March to May 2017. The study used an environmental design in the form of Completely Randomized Design (CRD) with two factors. The first factor is the location of explant position is abaxial (L1) and adaxial (L2). The second factor was the concentration of BAP 0 mg / L (B0), 2.5 mg / L (b1), and 5 mg / L (B2). The results showed that the position of eksplan gave an effect on mangosteen germination in vitro for its shoot length variables. The explant positions that had the best effect on the growth of in vitro mangosteen sprouts were adaxial. BAP concentration had an effect on germination of mangosteen in vitro for its bud growth and life percentage. 2.5 ppm of BAP concentration was the best concentration for mangosteen seed growth in vitro. There was no interaction between eksplan position and BAP concentration in all observed variables

Fertilization is one of efforts done by farmers to increase the production and quality of onions.  This research aimed to find out the effect of manure and NPK fertilizers to the growth and production of onions. This research was conducted in Paloh Lada Village, Dewantara Sub-district, North Aceh and Agroecotechnology Laboratory, Faculty of Agriculture, Malikussaleh University from May to July 2018. This research used Randomized Block Design (RBD) Factorial. The first factor was manure (P): 15 tons/ha (P1), 20 tons/ha (P2), 25 tons/ha (P3). The second factor was NPK fertilizers (N): 150 kg/ha (N1), 200 kg/ha (N2) and 250 kg/ha (N3). The results indicated that there was high significant interaction between manure and NPK fertilizers on wet weight and dry weight of onion bulbs and also bulb yield. The application of manure significantly enhanced the wet weight and dry weight of onion bulbs and its production and it also significantly increased the plant height at 14 days after planting. The application of NPK increased the wet weight and production of onion bulbs significantly. Also, the combination application of manure 15 tons/ha and NPK fertilizers 150 kg/ha did improve the wet weight, dry weight and production of onion bulbs.