Judul: Study Application Time of Calcium to Control Yellow Latex and Quality of Mangosteen Fruit (Garcinia mangostana L.).
Abstrak: Yellow latex on aryl and pericarp of mangosteen associated with low calcium content in fruit. Calcium is immobile nutrient, which its absorption is strongly influenced by transpiration. Therefore calcium soil application is needed to increase calcium content in the fruit. Application time of calcium have to be studied to maximizing calcium effects in reducing yellow latex on mangosteen fruit. The aim of this study was to study the application time of calcium to control yellow latex on manggosten fruit. The experiment was laid out on a randomized complete block design. There are eight treatments as follow: (1) no calcium fertilizer as control, (2) at anthesis stage, (3) at the beginning of stage 1 of fruit growth (14 days after anthesis), (4) at the end of stage 1 (28 days after anthesis), (5) at anthesis and the beginning of stage 1, (6) at anthesis and the end of stage 1, (7) at the beginning and end of stage 1, (8) at anthesis, beginning and end of stage 1. Application time of calcium at anthesis and the end of stage 1 effectively reduced yellow latex in aryl, pericarp, and increased calcium in endocarp. However calcium applications did not affect the physical and chemical properties of the fruit.
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Judul: Study to Control Yellow Latex and Pericarp Hardening of Mangosteen Fruit (Garcinia mangostana L.) with Calcium Spraying Aplication.
Abstrak: Calcium is one of important elements of cell membrane component and strengthen cell wall. Calcium is normally bound to pectin compound as a middle lamella component. Calcium deficiency affect the degradation of cell wall integrity. Low calcium content in the pericarp of mangosteen fruit could triggering the incidence of yellow latex or gamboges disorder on aryl and fruit pericarp. An experiment was conducted to determine the optimum combination of spraying frequency and concentration of CaCl2 in controlling yellow latex, pericarp hardening and quality of fruit. Factorial experiment was designed with two factors and three replications. The first factor was frequency of CaCl2 spraying that consist of three levels, i.e twice, four and six times. The second factor was calcium concentration that consist of four levels, i.e 0, 12, 24 and 36 g L-1. Result indicated that the combination of frequency of six times with 24 g L-1 is effective to reduce percentage of yellow latex in the aryl by 86% and 69% in the pericarp without pericarp hardening and reduction in fruit quality at harvest time and after 20 days storage
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Judul: Karakteristik Barisan Eksak Pendek HomR(N, ) dan HomR( ,N)
Abstrak: Module merupakan generaIisasi dari ruang ve}ctor, dimana pada ruang vektor skalar-skalamya berasal dati suatu lapangan (field) sedangkan pada module skaJar-skalamya merupalam unsur-unsur dan suatu ring R dengan unsur satuan. Dari suatu grup komutatif yang unsur-unsumya dipadukan dengan unsur-unsur dart suatu ring R, maka akan mengbastlk.an yang namanya R-module. Himpunan seroua fungsi homomorfisma yang memetakan dati R-module M ke R-module N dinotasikan sebagai HomiM,N), dimana HomiM,N) juga merupakan suatu R-module.
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