Internode Characteristics of Sweet Sorghum (Sorghum bicolor (L.) Moench) during Dry and Rainy Seasons in Indonesia

Abstract

: We have studied establishment of cultivation technique of sweet sorghum for monosodium glutamate (MSG) production on dry land in Indonesia, where the supply of raw materials has become restrictive recently. Previously, we confi rmed the feasibility of cultivation in this area during the rainy season. Meanwhile, cultivation during the dry season is also important because vast expanses of heretofore unirrigated fi elds have remained unused. The stem, which comprises internodes, is the main product of sweet sorghum used as a raw material by fermentation industries. This study analyzes differences in growth and yielding ability between dry and rainy seasons by comparing internode characteristics. A sweet sorghum cultivar -Wray -was cultivated in the rainy season from 1995 and in the dry season of 1996 in Madura Island of East Java, Indonesia. Stems of sweet sorghum cultivated during the dry season were shorter and lighter, with two fewer elongated internodes than those of plants raised during the rainy season. They accumulated sugar slower and to a lower peak, but they were inferred to be harvestable for a relatively long period during 30-60 days after anthesis. Through research of internode characteristics, the difference in stem length was inferred to result from differences in internode numbers (25%) and in individual internode length (75%). The difference in weight seemed to result mainly from the fewer elongated internodes. Further experiments must explore the cultivation period (sowing and ratoon crop), varieties, and planting density to establish a sweet-sorghum cultivation technique that is suitable for the dry season.

Year-Round Cultivation of Sweet Sorghum [Sorghum bicolor(L.) Moench] through a Combination of Seed and Ratoon Cropping in Indonesian Savanna

“…According to the previous research conducted in East Java, sweet sorghum grows better in the rainy season than in the dry season (Tsuchihashi and Goto, 2005). Furthermore, the present study demonstrated that plant height tended to be shorter toward the latter period of the dry season.…”

“…The 5 plants mentioned above were collected from the field during harvest and divided into individual internodes. Internodes longer than 1 cm were treated as elongated internodes (Tsuchihashi and Goto, 2005). The length of each internode was measured.…”

“…Considering the operational effi ciency of an MSG factory, it would be desirable to supply raw material throughout the year. Previously, we conducted fi eld experiments in the savanna area of Indonesia and confi rmed that sweet sorghum was cultivatable during the rainy (Tsuchihashi and Goto, 2004) as well as the dry season, although the yield during the latter period was lower (Tsuchihashi and Goto, 2005). Moreover, we examined the elongated internodes comprising the stem and reported shorter and lighter stems with two fewer elongated internodes.…”

“…Sweet sorghum also is more tolerant to drought than maize. This plant can thus, to a certain extent, resolve the problem of raw material for the MSG industry, and could contribute signifi cantly to East Javan agriculture if it were possible to cultivate it throughout the year in non-irrigable fields (Tsuchihashi and Goto, 2004;2005).…”

Relation between Stem Growth Processes and Internode Length Patterns in Sorghum Cultivar ‘Kazetachi’

“…The leaf number was defined as the fully expanded leaf number, not including expanding leaves. Tsuchihashi and Goto (2005) measured the height from the soil surface to the collar of the youngest expanded leaf as one parameter of stem elongation. They designated it as the stem length.…”