The use of pesticides is widely used in the production of citrus fruits for protection before and after harvest. The use of pesticides on a broad scale can pollute the environment and leave residues in plants and in plants such as fruit leaves and tubers. A survey was conducted to evaluate the level of pesticide residues in citrus fruits. The survey method is carried out by recording pesticide use by farmers and traders. The survey will be conducted in Dau, Batu and Poncokusumo Districts, Malang Regency by interviewing 10 farmers and 10 orange traders in each District. The Gas Cromatography method was carried out to measure the levels of pesticide residues tested at the Angler Biochemlab Laboratory, Surabaya. Descriptive analysis was used to analyze the levels of pesticide residues in citrus fruits then compared to the Maximum Residue Limit (BMR) through SNI 7313: 2008 quality standards on agricultural products. The residue levels of profenofos in farmer samples were found to be higher at 0.108 ppm compared to the sample from traders, namely 0.050 ppm at the Tegalweru village research site. In addition, traders in the village of Poncokusumo knew the imidaclroripid content was close to the maximum threshold of 0.040 ppm in farmer samples and 0.010 ppm in the merchant sample. Decreased levels of pesticide residues on food can be done with several approaches, namely physically and chemically. Reduction of pesticide residues in agricultural products can be done in several ways including by washing products with running water for several times or can also be done by soaking in water for one hour

This study aimed to evaluate changes in agronomic performances of some sweet potato cultivars planted in the rain-fed dry land and paddy fields. Completely randomized block design with three replications on a single factor of 12 sweet potato cultivars was done in two locations. The first location is the rain-fed dry land that formerly planted corn; located in Jatikerto, Kromengan District, and second is an irrigated paddy field that previously planted with rice, located in Wringinsongo, Tumpang District, Malang Regency. All cultivars that planted in both locations were applied to packaged standard cultivation technology for sweet potato. The parameters observed were storage root weight and vines weight (kg/plant), storage root yields and vines yield (t/ha), harvest index (%) and root/shoot ratio to describe the efficiency level of dry matter translocation to storage root. The results showed that there was a change of agronomic performance in sweet potato cultivars that planted between on the dry land and paddy fields, especially for storage root weight, storage root yield (t/ha) and root/shoot ratio. Changes in the sweet potato cultivation in the dry land to paddy fields are shown by an increase in storage root yields ranging from 2-4 times or reach 206-417%.

Ubi jalar (Ipomoea batatas (L.) Lam.) merupakan komoditas sumber karbohidrat setelah padi, jagung dan ubi kayu. Saat ini produktivitas ubi jalar nasional hanya sebesar 13,51 t/ha, lebih rendah dibandingkan  hasil penelitian yang mencapai 35 t/ha. Penelitian ini bertujuan untuk mengevaluasi karakter morfologi beberapa genotipe ubi jalar dan menganalisis jarak genetik genotipe-genotipe berdasarkan karakter kuantitatif. Hasil analisis kekerabatan dari 13 genotipe ubi jalar berkelompok pada 2 klaster (A dan B). Kemiripan antargenotipe didasarkan pada jarak Euclidean; terdapat dua kelompok genotipe yang memiliki nilai kemiripan tertinggi yaitu Beta 2--22 dengan Jago-OP-28, dan Beta 2--12 dengan Beta 2--15. Sepuluh variabel pengamatan yang mempengaruhi keragaman 13 genotipe tereduksi ke dalam empat komponen utama dengan nilai keragaman kumulatif sebesar 91,1%. Hasil analisis biplot dari 10 variabel pengamatan dengan menghilangkan empat variabel yang mempunyai vektor pendek mampu meningkatkan keragaman dari 59,7% menjadi 92,1%.

Defoliation of the leaves of sweet potato plants needs to be done to reduce the rate of vegetative growth, because the rate of vegetative growth that is not balanced with generative growth. The section of the sweet potato plant consists mainly of stems and leaves. The purpose of this study is to obtain sweet potato cultivars with criteria of tubers and stover yields through agronomic experiments with different defoliation and cultivars. Factorial Randomized Design by placing Cultivars as the first factor, (C) included: C₁ (Beta-2), C₂ (Kuningan Merah), C₃ (BIS OP-61-OP-22). The second factor of Defoliated (D), namely : D₁ (Defoliation 16 wap), D₂ (Defoliation 12 wap), D₃ (Defoliation 8 wap), with 3 replications. The results showed that: A high RGR value is followed by a large price URLˊ, meaning that the balance of new plant material is related to the ability of plants to carry out photosynthesis. Cultivar value Beta-2 RGR (8-4) = 71 mg.gˉ¹ dayˉ¹, Kuningan Merah URLˊ(8-12) = 65 mg.cmˉ². BIS OP-61-OP-22 cultivars produce large criteria (51.22 tubers/plot) and medium criteria (44.33 tubers/plot). Beta-2 cultivars produce small criteria (45.56 tubers/plot). Ratio F/R from BIS OP-61-OP-22 cultivars (high dual-purpose), cultivars Beta-2 and Kuningan Merah (high root production)

Global warming has changed global, regional and local climate conditions. Global climate change is caused, among others, by the increase in greenhouse gas emissions (GHG) due to various activities that drive the increase in the earth's temperature. Given that climate is a key element in the metabolic system, plant physiology and crop ecosystems, global climate change will adversely affect the sustainability of agricultural development. The impact of global climate change is the increasing population of pests on agricultural crops. One of the soybean pests whose population is increasing due to the increase in air temperature is the Bemisia tabbaci infestation. Increased pest populations of Bemesia tabbaci infestation in soybean crops cause dwarf leaves of dwarf plants and threatens to increase soybean production. Efforts to overcome the impact of global warming is mainly due to increased pest populations, it is necessary to think and seek breakthroughs to anticipate the explosion of pest populations in soybean crops, among others by: the optimization of natural control, physical and mechanical control and cultivation techniques. The combination of techniques or tactics of the optimal component of soybean pest control technology is established on the basis of appropriate information knowledge about soybean pest, ecosystem and socio-economic based on IPM approach.