dc.description.abstract | Demand of rice in Indonesian will continuously increase following the population growth. Increasing demand of rice must be balanced by improvement of rice productivity. One of efforts that can be done to increase rice productivity is by improving soil properties either physically, chemically and biologically. Addition of organic matter may improve soil properties, but organic matter such as compost and manure is needed in large amounts. Humic substance is known able to replace a part of organic matter role. Treatment of humic substance on soil and plant is expected to be able to improve productivity of rice. The aim of this research was study effect of humic substance on growth and productivity of rice by different method and dosage application. The research was conducted at Sidosari village, Natar District, South Lampung Regency using Ciherang rice variety. Fertilizers used were 350 kg/ha Phonska, 200 kg/ha Urea, and 100 kg/ha SP-18. The treatments were composed of treatment of without humic substance, humic substance addition to soil, and humic substance addition to soil and leaves. Addition of humic substance to soil conducted on land preparation, while addition of humic substance to the leaves was done when the plants were 2 to 8 week after transplanting with an interval of two weeks. Humic substance dosages were 15 l/ha that diluted to 4 ml/l for soil and 2 ml/l for leaves. The results showed that the growth and yield components increased in plants treated with humic substance. The weight of grain yield of the plant without humic substance equivalent to 6.7 ton/ha, whereas that of plant with humic substance addition to soil was 7.14 ton/ha, and that of plant with humic substance addition to soil and leaves was 7.86 ton/ha. | en |