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The problem of plant cultivation in dry upland with slope of >15° is the high soil erosion that result in high rate of sedimentation in the downstream of watershed. One way of overcoming this problem is by utilization of mulches. The objective of the experiment was to study the effect of mulch application on growth and yield of chilli (Capsicum frutescensL.).The experiment was conducted from January 2010 until June 2011 at Selopamioro micro watershed at Imogiri Subdistrict, Bantul District, Special Region of Yogyakarta. The experiment was arranged in a randomized complete block design consisted of four mulch treatments (rice straw, litter, plastic/silver black polyethylene, and without mulch) and four replications. The observed variables were the growth parameter (plant height), soil moisture content, soil temperature, and yield (number and weight of chilli). The result showed that application of mulches did not affect plant height and yield of chilli, but increased number of fruit. The best mulch for chilli crops in upland area was rice straw, that yielded the highest increase in number of fruit. Mulch as a soil conservation practice reduced runoff coefficient, while dicharge and extended of the reponse time were reduced only at rainfall less than 21 mm.

The successful of gene transformation on crop plants depends on the ability of explant to develop somatic embryos. The effect of medium composition on induction and proliferation of embryonic callus was analyzed on several soybean genotypes, including low irradiance (LI) tolerant genotype (Ceneng, Pangrango C6-30-10 and C6-76-10) and two LI sensitive genotypes (Godeg and Slamet). Immature cotyledons (14 DAA) were cultured in induction medium including MSIA (MS, vitamin B5, 30% sucrose, 0.2% gelrite, 10 mg L-1 2,4-D and 10 mg L-1 NAA) and MSIB (MS, vitamin B5, 30% sucrose, 0.2% gelrite, and 40 mg L-1 2,4-D). Embryonic calli was subcultered one month after initiation onto proliferation medium including MSIIA (MS, vit. B5, 30% sucrose, 0.2% gelrite, 5 mg L-1 2,4-D and 5 mg L-1 NAA) and MSIIB (MS, vitamin B5, 30% sucrose, 0.2% gelrite, and 20 mg L-1 2,4-D). The result showed that percentage of callused explant was 76-94% and the highest initiation obtained on Pangrango genotypes. The average of calli diameter at 1 month after initiation was 0.5-1.2 cm. Calli which was obtained on MSIA medium showed yellow, tranparent, and friable, whereas calli was obtained on MSIB medium showed yellow-brown, transparent, and friable. Increasing calli diameter and structure were obtained on proliferation medium. The combination of 2,4-D and NAA on MSIA and MSIIA both are induction and proliferation medium respectively were better than MSIB and MSIIB which were contain only 2,4-D. Ceneng genotype showed best performance of somatic embryogenesis than others, and Slamet genotype showed lowest response both on callus induction and proliferation.