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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.

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.

Mite (Tetranychus urticae) that attacks the cassava plants during dry season can reduce the yield up to 53%, depending on plant age and duration of attacks. The objective of the trial was to evaluate the cassava promising clones for tuber root yield and mite resistance. The field trial was done in Malang, East Java, Indonesia, in 2018 with fifteen clones using a randomized complete block design, with three replications. The glass house experiment for mite evaluation was done in Malang in 2018. A total of fifteen clones were used in this glass house trial. Infestation of mite (imago) was done 1 month after plating with 15 mites/pot on the lower part of the fourth or fifth leaf. Results of the field experiment showed that there was a genetic variability in the clones tested. The fresh tuber yield in 10 months ranged 30.33–55.67 t/ha with mean 41.34 t/ha. The fresh tuber yield of clone OMM 0915-11 was the highest of 55.67 t/ha. The tuber result of clone UJ5d50-207-3 similar to OMM 0915-11 and significantly higher than check variety UJ5. Response of clones to mite attack were as follows: two clones were resistant, ten clones were moderately resistant, and the other clones were susceptible. Based on the green house trial, the response of clones to mite attack was as follows: one clone was highly resistant, two clones were resistant, ten clones were moderately resistant, and the other clones were susceptible. Clone OMM 0915-11 was resistant variety or high resistant variety based on the green house and field experiments, while clone UJ5d50-207-3 was moderately resistant based on both glass house and field experiments. [ABSTRACT FROM AUTHOR]

Early maturity, small seed size, and high seed yield are important characters of mungbean in Indonesia. The objective of the study was to determine the useful parents in mungbean crosses for early maturity, small seed size, and high seed yield varieties by estimating the genetic parameters and their inheritance. The study was conducted at the ILETRI, Malang, East Java, Indonesia, during the dry season of 2014. 20 F1 and 5 parents were evaluated using a randomized block design, repeated three times. Results of the study showed that all observed traits showed the importance of both additive and dominance gene effects. The relative value of general combining ability (GCA) was greater than specific combining ability (SCA) for number of pod clusters per plant, number of branches per plant, plant height, days to maturity, and 100-seed weight which indicated the importance of additive gene effect. The dominance gene effect occurred on number of pods and seed yield per plant. Among five parents, G3 was the best combiner for all the observed characters except pod length; therefore, G3 could be exploited for late maturity, small seed size, high number of branches and pod cluster, and high seed yield. G5 has a high GCA for 100-seed weight. G1 and G2 have good GCA for early maturity. G3 and G5 genotypes are useful as parents in mungbean breeding for small and large seed size varieties, respectively. The best combination for seed yield was G2 × G3 and G3 × G1 crosses and could be proceeded with selection for early maturity, small seed size, and high seed yield varieties. [ABSTRACT FROM AUTHOR]