Use of Natural Products on the Control of Aspergillus flavus and Production of Aflatoxins In Vitro and on Tomato Fruit

Aspergillus flavus affects fresh and dry fruit and vegetable products, and its toxic metabolites, namely aflatoxins, cause serious damage in humans. The objective of this research study was to evaluate the effect of commercial natural products as well as edible and nanostructured chitosan coatings on the development of A. flavus and on the production of aflatoxins in vitro and in tomato. Treatments were as follows: chitosan 1%, chitosan coating, chitosan nanostructured coating, Citrocover 1% (citrus seed extract), Resinadher 0.5% (pine resin extract), mancozeb 2%, and water. The variables were as follows: halo inhibition, spore production, and aflatoxins content. In fruit, the following were evaluated: disease incidence, mycelial growth, and aflatoxin production. An ANOVA (Tukey: p < 0.05) was used. In vitro results showed that Citrocover and Resinadher reduced sporulation (0.2 and 0.9 × 105 spores mL−1, respectively), while chitosan inhibited the production of aflatoxins. With Resinadher and Citrocover, tomato fruit had the lowest incidence, mycelial growth, and aflatoxin production with corresponding values of 0%, 0.0 cm2, and 0.95 ppb, respectively, and 7%, 0.2 cm2, and 1.77 ppb, respectively. The use of Citrocover and Resinadher could be a viable alternative to decrease the development of A. flavus in tomato fruit.

UJI VIABILITAS TERHADAP BENIH POLYEMBRIONI

Seeds are mature ovules. One or more of the ovaries formed in the legume, but never more than one seed formed in the ovaries of monocots. Each ripe seed always consists of at least two parts, namely: (1) Embryo, (2) Seed coat (Seed coat or testa). Embryo is formed or derived from fertilized eggs (zygote) by undergoing cell division in the embryo sac. Seed coat is formed from the integument (one or more) of the ovules. In legumes generally there are two layers of seed coat. Every very young and growing seed always consists of three parts: (1) Embryo, (2) seed coat, (3) Endosperm. Endosperm is a storage food storage network which is absorbed by the embryo before or during seed germination and is always present in very young seeds. Polyembryonics is the presence of more than one embryo in one seed, but these embryos do not always mature or mature, remain undeveloped or degenerate. The purpose of this research is to study the germination of one seed that has more than one embryo and to determine the growth of seedlings from polyembryonic seeds. The results showed that the highest plant growth (plant height, number of leaves, fresh weight and dry weight of orange seeds) was found in orange seeds that had 1 embryo compared to orange seeds which had 2 and 3 embryos. Seed germination and growth is strongly influenced by the amount of food reserves stored in seeds (Magagula and Ossom 2011 in Hasnah M, 2013). Keywords: Citrus Seed, Polyembrioni, Seed Viability

Perbanyakan Tanaman Jeruk Siam (Citrus nobilis L.) dengan Teknik Kultur in vitro Menggunakan Biji Tanaman Terinfeksi Penyakit Citrus Vein Phloem Degeneration (CVPD)

Citrus (Citrus nobilis L.) Propagation Through Culture In Vitro Using Seed From Infected Plants Of Citrus Vein Phloem Degeneration (CVPD) Disease. The sample was taken in Belancan Village, Kintamani District, Bangli Regency, and invitro culture was conducted in UPT. Genetics Resource and Molecular Biology Laboratory in February to June 2018. This research purposes were to get the new citrus plant from citrus seed infected of CVPD disease explants with culture in vitro and found the presence of the bacterium Liberobacter asiaticus in results of citrus plants culture in vitro. The sampling method is using plants appearance. Obtained sample 1 is a plant that shows severe symptoms of CVPD disease and sample 2 plants that show no symptoms of CVPD disease. Seed Sample is cultured with MS0 medium for 8 WAP then proceed to acclimatization. The results of this research showed that the seed explants from both samples were able to grow well and did not have the characteristic of CVPD disease, but explant seed sample 2 in vitro culture result showed that the bacterial DNA bacterium Liberobacter asiaticus pathogen CVPD disease does exist in length 1160bp, so it cannot be expected to produce CVPD-free crops.