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The evaluation of the diversity in the cowpea local varieties (CLVs) allows the efficient use of genetic resources for cultivar development. This study aimed to evaluate the diversity of CLVs based on observation of morphological characteristics and to identify the relationship among morphological traits and potential varieties as donor genes to improve yield potential. The CLVs were collected from five provinces in Indonesia during 2017–2018. The evaluation of the performance of CLVs’ morphological characteristics was carried out in the Indonesian Legumes and Tuber Crops Research from March to July 2019. The observed data were 43 agronomic characters which consist of qualitative and quantitative characters. There is a high variation in stem pigmentation and seed color in 214 CLVs. There were nine qualitative characters with no variation. Most quantitative characters showed significant variation among CLVs. The clustering of 214 CLVs results in five clusters in which some CLVs maintain valuable characteristics that could be used in the breeding program. The number of pods per plant, number of racemes per plant, and 100 seed weight were useful for indirect selection in the yield improvement. Based on the genotype by trait biplot, the CLV 112, 191, and 111 could be used as donor parents for seed size improvement and the CLV 169 could be used as a donor parent for the yield potential improvement in the cowpea breeding program. Four cowpea genotypes can be recommended for commercial release or used as potential breeding material in cowpea cultivar development programs. The new findings of this study could provide a basis for the genetic improvement of cowpea.

Sweet potato weevil Cylas formicarius (Fab.) is the main obstacle for sweet potato production in various countries. Root damage caused by C. formicarius larvae reduced root yield up to 100%. The aim of this study is to test the measures using mulch and entomopathogenic fungus Beauveria bassiana for controlling C. formicarius in endemic land of entisol type. The control measure tested was the use of straw mulch and plastic mulch as well as the application of the entomopathogenic fungus Beauveria bassiana. The research was conducted at the experimental station at Indonesian Legumes and Tuber Crops Research Institute, Malang from July to December 2018. The results showed that the measure for controlling C. formicarius using straw or plastic mulch combined with the entomopathogenic fungus B. bassiana produces root yields between 17 and 26 t/ha. Using plastic mulch as a cover for mounds with the application of the fungus B. bassiana is more effective and efficient in controlling C. formicarius than the insecticide deltamethrin. Plastic mulch can physically inhibit the process of laying eggs and the formation of C. formicarius larvae, while B. bassiana is toxic to eggs, larvae, and adults of C. formicarius. The efficacy of control measure using plastic mulch and the application of B. bassiana can reduce yield losses by up to 96.76%. Technological innovation using plastic mulch to cover the mound with the application of the entomopathogenic fungus B. bassiana can be recommended to control C. formicarius on land endemic to the entisol type.

Since 2020 porang (Amorphophallus muelleri Blume) has been declared as an important commercial crop grown in Indonesia. Recently, porang tubers a coated of a distinct white waxy substance was observed at seed storage. The symptoms pose a threat to tuber vigour quality due to the intensive infestation on stored tubers. This sap- sucking insect sucks the juice leading to desiccation and shrivelling of tubers. This study aims to identify the sap- sucking insect pest attacks the storage porang tubers. The studies carried out at ILETRI. Identification of the caused insect species was done by observing symptoms visually, morphological identification of adult females using Compound microscope Olympus Bx43 in 40 X magnification, and tuber germination and growth of 250 infested tubers in the field. Regarding to the specific symptoms whose soft body coated of a distinct white waxy substance and morphological measurement of the average length of the adult females (862.62±46.3 μm with range between 764 - 904 μm), it’s supposed caused by mealybug in Rhizoecus amorphophalli (Hemiptera:Pseudococcidae). Our founding revealed that R. amorphophalli is first discovered as causal agent of a mealybug pest of porang in Indonesia and turned out to be very detrimental because their infestation caused 90 percent of infested porang tubers unable to germinate and grow.

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 highyielding cassava varieties and fertilization technology packages to the growth and yield of cassava in the acid dryland of Sukaharja Village, Warung Kiara Sub-district, Sukabumi Regency, West Java. The contents of organic carbon, nitrogen, and magnesium in the soil are 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, fresh 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 qualities were 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 content. [ABSTRACT FROM AUTHOR]

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Cassava is responsive to fertilization, and it is one of the important factors for high productivity. Root formation needs sufficient Phosphorus (P) and Potassium (K) nutrients, and adequate nutrients uptake increases root weight and starch content. However, the optimum effect of P and K fertilization should be balanced with Nitrogen (N) fertilization. The objective of the study was to determine the effect of mixed (inorganic and organic) fertilizers doses on the growth and yield of several cassava cultivars grown in Pati district, Central Java, Indonesia. The experiment was carried out during planting season in 2018. Four cassava cultivars (Litbang UK 2, UK 1 Agritan, Malang 4, and UJ 5) were tested under five doses of mixed fertilization. The split-plot design with three replicates was used in this experiment, where fertilizations as the main plot and cultivars as the subplot. The results showed that mixed fertilization had no significant effect, while the cultivars had a significant effect on growth and yield parameters as well as starch content. No significant interaction effect of the two factors, except in plant height. [ABSTRACT FROM AUTHOR]

The increasing and stabilizing of soybean product in Indonesia face many limitations. One of the limiting factors is pod borrer (Etiella zinckenella Treitschke) infestation that is able to cause yield loss up to 80%. Objective of the research was to find out some advanced soybean lines that resistant to pod borrer. Design was randomized complete block with three replications. Soybean lines were grown gradualy to ensure the simultanously flowering. The plants were caged at 35 days after planting (DAT) and infested with the imago of E. zinckenella at 56 DAT. Results showed that different soybean lines affected imago population, eggs population, larvae population, infected pods and infected seeds. Some genotypes were consistantly resistant to E. zinckenella. The resistance of those genotypes were non preference resistance based on eggs population, larvae population, infected pod and infected seeds. This study discovered nine soybean lines that is resistant to E. zinckenella, so that it can be beneficial for improving soybean resistance to this pest through releasing as a new resistant pod borer variety after tested further in potential yield and genetic x environment interaction trials. In addition, there were three varieties and two germplasm accessions that can be used as gene sources for improving the resistance of the varieties. The three varieties are able to be cultivated directly in field to decrease the E. zinckenella occurrence. [ABSTRACT FROM AUTHOR]