Evaluasi Teknis dan Manajerial Kegiatan Pemupukan Kelapa Sawit di Kabupaten Landak, Kalimantan Barat

Aktivitas pemeliharaan tanaman kelapa sawit merupakan upaya yang sangat penting dalam meningkatkan produktivitas yang optimal. Salah satu upaya dalam meningkatkan produktivitas yaitu dengan pemupukan. Pemupukan merupakan proses penambahan unsur hara dan perbaikan struktur tanah serta penggantian unsur-unsur hara yang hilang. Pemupukan harus sesuai dengan dosis yang telah ditentukan dalam buku rekomendasi pemupukan dan tepat waktu pemberiannya. Penelitian bertujuan mengevaluasi kegiatan pemupukan tanaman kelapa sawit berdasarkan efektivitas pemupukan. Kegiatan dilaksanakan pada Februari hingga Mei 2019 di Kabupaten Landak, Kalimantan Barat. Metode yang dilaksanakan selama kegiatan penelitian yaitu metode langsung dan metode tidak langsung. Percobaan disusun menggunakan uji t berpasangan terhadap pemupukan berbagai jenis pupuk yang berbeda pada kelapa sawit. Pengamatan dilakukan terhadap keefektifitasan pemupukan meliputi kaidah 6T (tepat jenis, tepat dosis, tepat waktu, tepat cara, tepat tempat, dan tepat alat), prestasi kerja dan gejala defisiensi unsur hara. Hasil pengamatan menunjukkan gejala defisiensi unsur hara secara visual menunjukkan tanaman kelapa sawit masih mengalami kekurangan unsur Magnesium (Mg), Kalium (K), Boron (B), dan Nitrogen (N). Kata kunci: defisiensi, efektivitas, rekomendasi, unsur har

Resistance to thrips in pepper

Pepper (Capsicum) production is constrained by heavy infestations of thrips, causing direct and indirect (by transmitting viruses) damage. Thrips control using chemical insecticides, biological agents, culture practices and integrated pest management has limited success. The availability of thrips-resistant varieties would increase the effectiveness of thrips control and may also delay and reduce the transmission of viruses. This thesis is aimed at obtaining more knowledge regarding thrips resistance in pepper, including the identification of new sources of resistance, the elucidation of resistance mechanisms, identification of factors contributing to resistance and a QTL analysis. We developed several test methods to evaluate plant resistance to thrips and showed that in vitro tests correlate well with greenhouse tests. We used these methods to test a collection of Capsicum accessions of widely different origin and crop types. This resulted in the identification of a few accessions (mostly C. annuum) with high levels of resistance to two thrips species: Frankliniella occidentalis and Thrips parvispinus. Since C. annuum is the most widely cultivated species, the finding of resistance in C. annuum is means that the resistance can be easily introgressed through conventional crossing and selection. The effect of resistance in pepper on thrips reproduction and development was studied using three highly resistant, three medium resistant and three susceptible accessions selected based on damage ratings. Adult and pre-adult survival, developmental time and reproduction rate were assessed in a detached leaf system. Resistance factors in leaves of resistant pepper accessions were shown to have significant effects on oviposition rate, larval mortality and life-cycle period, indicating that this resistance is based on antibiosis. In order to map QTL for resistance we developed an F2 population from the cross between a susceptible C. chinense accession and the resistant C. annuum AC 1979. A genetic linkage map for this population was based on AFLP and SSR markers, where the SSR markers served to assign and orient most linkage groups to pepper chromosomes. As larval stages were highly affected by resistance in pepper leaves, damage caused by larvae and larval survival were used as parameters to detect QTLs conferring resistance to thrips. Interval mapping detected one QTL for each of these parameters, all co-localizing near the same marker on chromosome 6. This QTL explained about 50% of the genetic variation, and the resistance allele of this QTL was inherited from the resistant parent. No other resistance QTLs were detected in this population. Since resistance to thrips was clearly expressed in pepper leaves we proceeded to study leaf traits that may contribute to resistance. Morphological leaf characters and metabolites have frequently been linked with resistance to thrips in other plant species. However, we found no convincing evidence that any of these traits played a role in thrips resistance in pepper. In the F2 mapping population we found no correlation and no QTL co-localization of resistance with leaf morphological characters previously linked to resistance in pepper against insect pest and in other plant species against thrips e.g. color, toughness, trichome density, and cuticula thickness. GC-MS (Gass Chromatography – Mass Spectrometry) analysis of the three resistant, three intermediate and three susceptible accessions mentioned above showed that seven metabolites were correlated with resistance to thrips and six compounds with susceptibility. However, when we applied GC-MS and LC-MS (Liquid Chromatography – Mass Spectrometry) to leaves of the F2 mapping population, we found no strong correlation between resistance and any detected metabolites. Two metabolite QTLs co-localized with the resistance QTL. However, these QTLs explained only a small proportion of the variance and the co-localization was not supported by strong correlations of the metabolites with resistance. This suggests that the major resistance factor(s) in pepper against thrips may not or only partially be determined by the presence or absence of specific metabolites. This thesis provides a strong basis for the development of thrips resistant pepper varieties through introgression of the resistance QTL region on chromosome 6 originating from resistant C. annuum accessions. However, the effect of resistance QTL on chromosome 6 should be confirmed in another population such as a population of F3 lines. In vitro leaf assay can be used as evaluation methods in pepper breeding program. This has the advantages of minimizing the risk of contamination and of controlled environmental conditions. Elucidation of factors contributing to resistance should be continued by giving attention to other possibilities such as proteins, specifically proteinase inhibitors, or other leaf anatomical and morphological traits. Also other extraction and detection methods may be used to discover other metabolites that might be related to resistance. Finally, for practical applications it is necessary study how to use the antibiosis based mechanism against thrips found in this thesis in thrips control and/or management practices. </p

Genetic variability and stability analysis of chili in three environments

Chili is an important vegetable crop consumed by most Indonesian people. Chili production is affected by the limited varieties and low adaptability to growing in different environments. This study aimed to identify the variability of 22 chili pepper on morphology, the genotype x environment interaction, and the stability of 10 chili pepper genotypes in 3 different environments. The study was conducted from July 2020 to February 2022 in Sleman DIY, Bogor, and Blitar. The experimental design used a single-factor randomized complete block design, each consisting of three replicates. The genotypes evaluated were HCR 17-003, HCR 17-004, HCR 17-007, HCR 17-008, HCR17-012, HCR 17-013, HCR 17-014, HCR 17-017, F7-1, F7-2, F7-3, Ca011, Ca013, Ca020, Ca021, Cf002, Cf005, Cf007, Cf010, Cf015, Bonita, and Loblita. Ten genotypes were evaluated in stability analysis, i.e., PKHT A, PKHT B, Bara, Genie, Centil, PKHT C, PKHT D, Bonita, Sona, and Tunduk. The biplot analysis for genetic diversity study showed a total diversity was 40.5% for the two main components. The genotype x environment interaction had a significant effect on productivity. PKHT C and Sona were identified as stable based on the Francis-Kannenberg method. PKHT C, Sona, PKHT B, and Bonita were stable based on the Wricke method. PKHT A and Bonita were stable based on Finlay-Wilkilson methods. PKHT B, PKHT C, Sona, and Bonita were identified as stable based on the AMMI method. The genotype which is stable based on all stability methods was PKHT C. Keywords: AMMI; GxE interaction; parametric stability; variety

Perbanyakan Ruskus (Ruscus Hypophyllum L.) secara In Vitro

These experiments were aimed to obtain optimum medium for micropropagation of Ruscus. There were two experiments consist of in vitro shoots proliferation, shoot elongation and rooting. The experiment of shoot proliferation performed by inducing adventitious shoots from explant in the Murashige and Skoog (1962)(MS) basal medium supplemented with combination of plant growth regulators BAP (0.0, 0.5, 1.0, 2.0, 4.0 and 6.0 mg/l) and IAA (0.0, 0.1, 0.2 and 0.4 mg/l). The elongation and rooting of plantlets were induced in the different concentration of the MS basal medium (0.5, 1.0 and 2.0 strength) combined with IBA (0.0, 1.0, 2.0, 3.0 and 4.0 mg/l). Both experiments were arranged as completely randomized design with 15 replications. Adventitious shoots were produced in all medium supplemented with BAP with or without IAA. However MS medium supplemented with BAP 1 mg/l or 2 mg/l combined with IAA 0.2 mg/l were the best. The number of adventitious shoots in these medium were 9.2 and 9.4 shoots after 8 weeks cultured respectively. Increasing concentration of BAP more than 4 mg/l decreased number and size of adventitious shoots. The plantlets produced in the proliferation medium were then transferring to the next treatments for elongation and rooting. The best medium for elongation and rooting were medium with half strength of MS with or without IBA. Acclimatization conducted by transferring the rooted plantlets on the medium containing sterilized soil and rice husk charcoal (1:1). After 4 weeks acclimatization, 60-100 percent of plantlets were survived and growth, depend on treatments

Seleksi dan Kemajuan Seleksi Karakter Komponen Hasil pada Persilangan Cabai Keriting dan Cabai Besar

Selection is very important activity in plant breeding program. The purpose of this study was to obtain genetic information, heritability and expected genetic advance, and to compare the genetic advance expectations with the selection advance. The research was conducted from September 2013 to November 2015 at Research Station of Leuwikopo, Dramaga, Bogor. Distribution of F2 population data in this study was broader than that of F3 populations. Broad sense heritability estimated by F3 populations showed in agreement to that estimated by F2 population. Character of fruit weight, fruit length, pedicel length and yield had positive value of selection advance appropriate to the genetic advance expectations in F2 populations. The value of heritability estimate and genetic advance were high indicating that the phenotypic variances were controlled by action of additive genes

Determination of anthracnose (Colletotrichum gloeosporioides) resistance group in shallot (Allium cepa var. aggregatum)

Shallot anthracnose, caused by Colletotrichum gloeosporioides, is a devastating disease in a tropical country with high humidity and rainfall. Chemical control of anthracnose is neither economical nor eco-friendly, and genetic resistance is considered an efficient management method. This study aimed to determine the resistance groups of several shallot varieties and predict resistance heritability characteristics. In this study, a total of 13 Indonesian shallot varieties were evaluated for anthracnose resistance and separated into two groups, resistance and susceptible, based on K-means clustering developed by using disease resistance/susceptibility characteristics such as incubation period, disease incidence, disease severity, and spot diameter. The results indicate that the Agrihorti, Maja Cipanas, Batu Ijo, and Rubaru varieties were identified as resistant groups based on lower disease severity and incidence, smaller spot diameter, and longer incubation period. Maja Cipanas and Rubaru were more consistent in all variables, which is recommended as a source of genetic resistance genotypes. On the other hand, the Biru Lancor, Bima Brebes, Srikayang, Violetta, Slupu Merah, Pancasona, Sakato, Katumi, and Kuning varieties were identified as susceptible groups based on high disease severity and incidence, large spot diameter, and short incubation period. Keywords: susceptibility characteristics, genetic resistance, k-means clustering, disease severit

Diallel Analysis of Chili Pepper Resistance to Melon Aphid (Aphis gossypii Glover) Infestation in Seedling Phase

Aphis gossypii Glover is one of important insect pest in Indonesia. Genetic analysis of resistance to A. gossypii is required in plant breeding program to obtain host-plant resistance cultivar. Diallel analysis was used to estimate genetic parameters for chili pepper resistance to A. gossypii infestation in early generation. The objective of this research was to estimate genetic parameters of chili pepper resistance to A. gossypii infestation with diallel crossing design. The F1 and parent plants were arranged in randomized competed block design with three replication. Resistance lines was measured using choice test laboratory screening techniques. Two aphids were infested per plant and stopped 12 days after first infestation. Different lines respond was detected as shown by significant numbers of aphid per leaf, total aphid per plant, and total winged aphid per plant. There were no maternal effect and resistance were controlled by recessive and polygenic genes. Gene effects for resistance to aphid’s infestation were additive and dominance. Dominance effect larger than additive effects. Broad-sense heritability values were high but narrow-sense heritability values were very lo

Comparative analysis of Genetic Diversity among Pod Vegetables Genetic Resources Potential in Indonesia Revealed by ISSR Markers

Cowpea (Vigna unguiculata ssp unguiculata), yardlong bean (Vigna unguiculata ssp sesquipedalis), Bambara groundnut (V.subterranea), lima bean (Phaseolus lunatus), bush bean (P. vulgaris), jack bean (Canavalia ensiformis), velvet bean (Mucuna pruriens) and winged bean (Psophocarpus tetragonolobus) are the important pod vegetable of the legume crop in Indonesia. These crops have a high economic and nutritional value. Its dry seeds are rich in proteins just like soybeans that can support human health and future food supply. The genetic diversity among different pod vegetables is not very well known. The objectives of this research were to determine the genetic relationships among different pod vegetable species based on ISSR markers. 32 accessions were analyzed by 11 ISSR primers. The result showed that the ISSR marker generated 80 DNA band with the polymorphism rate of 100% and the informative primers were PKBT 3 and PKBT 6. The result of cluster analysis and PCA analysis grouped all 32 accessions of the vegetable pod into eight clusters, indicating that the majority of the accession of a given species tend to group. Gower's similarity coefficient among all accessions varied from 0.425 to 0.988, and from 0.444 to 0.700 at the species level. The ISSR markers revealed the close relatedness between V. subterranea - C. ensiformis&nbsp;species, while the greatest distance was found between the P. vulgaris - M. pruriens species. Such a determination of relatedness is useful for a better understanding of the relationships among different pod vegetable species, which are generally considered to be a complex group with high phenotypic variability. &nbsp; Keywords: clustering, genetic distance, polymorphism, pulses, similarity coefficientKacang tunggak (Vigna unguiculata ssp unguiculata), kacang panjang (V. unguiculata ssp sesquipedalis), kacang Bogor (V. subterranea), koro kratok (Phaseolus lunatus), kacang merah (P. vulgaris), koro pedang (Canavalia ensiformis), koro benguk (Mucuna pruriens) dan kecipir(Psophocarpus tetragonolobus) merupakan sayuran polong penting di Indonesia dari tanaman kacang-kacangan. Tanaman tersebut bernilai ekonomi tinggi dan kaya nutrisi dengan kandungan protein biji keringnya yang hampir sama dengan kedelai dan dapat menunjang kesehatan manusia sekaligus menunjang pangan di masa depan. Informasi keragaman genetik di antara sayuran polong yang berbeda masih terbatas. Penelitian ini bertujuan untuk menganalisis keragaman genetik dalam dan antar sayuran polong yang berbeda spesies berdasarkan marka ISSR. Sebanyak 32 aksesi sayuran polong dianalisis menggunakan 11 primer ISSR menghasilkan 80 pita polimorfik dengan persentase polimorfisme sebesar 100% dan primer informatif yang didapat adalah PKBT 3 dan PKBT 6. Hasil analisis kluster dan analisis PCA mengelompokkan 32 aksesi tersebut ke dalam delapan kluster dan menunjukkan mayoritas aksesi yang satu spesies mengelompok bersama. Koefisien kemiripan genetik Gower keseluruhan aksesi berkisar antara 0.425-0.988, dan koefisien kemiripan delapan spesies berkisar antara0.444 – 0.700. Hubungan kekerabatan antara spesies V. subterranean - C. Ensiformis memiliki jarak genetik terkecil, sedangkan jarak genetik terbesar ditemukan antara spesies P. vulgaris - M. pruriens. Penentuan kekerabatan tersebut bermanfaat untuk pemahaman yang lebih lanjut tentang hubungan di antara sayuran polong yang berbeda spesies, yang umumnya dianggap sebagai kelompok yang kompleks dengan variabilitas fenotipik yang tinggi. Kata kunci: jarak genetik, kacang-kacangan, koefisien kemiripan, pengelompokan, polimorfism

In Vitro Polyploidy Induction of Patchouli (Pogostemon Cablin Benth.) by Colchicine

Patchouli (Pogostemon cablin Benth.; 2n = 32) is an aromatic herbaceous plant commonly cultivated for use in the the fragrance industry. As patchouli is propagated by cuttings polyploidization induction by colchicine treatment was conducted to obtain a new genotype with high patchouli alcohol content. This research aimed to increase patchouli genetic diversity with colchicine treatment by the formation of a polyploid plant. Axillary buds from single node cutting of aseptic plantlets were used as the explants. The experiment was arranged using a factorial completely randomized design with two factors, namely the concentration of colchicine and the immersion duration. Genetic diversity of patchouli was successfully enhanced by adjusting the colchicine concentration and immersion treatment. lethal concentration (LC) of 50% in patchouli was 0.132% and the LC 50% for soaking time was 60.16 hours. The number of chloroplasts, stomatal length and chromosome number increased with increasing ploidy, whereas stomatal density and the number of trichomes decreased. The chromosome number of 16 patchouli mutants in generation 4 was still unstable, and a chimera was found with mixoploidy between 20-80. A hierarchical dendogram clustered 16 patchouli mutants into four different groups