Seaweed and seaweed-derived products have been widely used as bio stimulants in crop production due to presence of multiple growth regulators such as cytokinin, auxins, gibberellins, betaines, as well as presence of macronutrients such as Ca, K, P, and micronutrients like Fe, Cu, Zn, B, Mn, Co and Mo, which are necessary for plant growth and development. Numerous studies have revealed a wide range of beneficial effects of seaweed extract on plants, such as early seed germination and establishment, better crop performance and yield, inducing resistance to biotic and abiotic stress and many more. This paper is an effort to review the importance of seaweed extract on germination, production, improvement of nutritional quality of agricultural crops which helps in further study of sea weed in agriculture.

A field experiment was conducted during the three consecutive seasons from 2006-08 on clay loam soil of Sugarcane Research Station, Buralikson, Assam to study the effect of different herbicides along with other cultural practices of weed management of sugarcane. The experimental field was laid out in randomized block design with three replication with the following ten treatments viz. T 1 : control, T 2 : 3 hoeings (1 st , 4 th and 7 th week), T 3 : Atrazine@ 2kg a.i/ha + 2,4-D @ 1kg a.i/ ha at 45 days after ratoon initiation, T 4 : atrazine @ 2 kg a.i/ha + 1 hoeing at 45 days after ratoon initiation, T 5 : metribuzine @1 kg a.i/ha + 2,4-D @1 kg a.i/ha at 45 days after ratoon initiation, T 6 : metribuzine @1 kg a.i/ha + 1 hoeing at 45 days after ratoon initiation , T 7 : glycel-41@ 0.4 kg a.i/ha at 3 rd week stage, T 8 : glycel-41@ 0.4 kg a.i/ha at 3 rd week + 1 hoeing at 60 days after ratoon initiation, T 9 : trash mulching in alternate rows + hoeing during 1 st and 6 th week, T 10 : trash mulching in all rows. Result revealed that all the weed management practices had a significant effect on growth and yield of sugarcane over control. Out of all treatments, pre-emergence spraying of metribuzine @1 kg a.i/ha followed by spraying of 2, 4-D @1 kg a.i/ha at 45 days after ratoon initiation recorded lesser number of weeds and weed dry weight with higher weed control efficiency (80.38%). The same treatment also recorded the higher cane yield (79.6 t/ha) which is followed by pre-emergence spraying of metribuzine @ 1 kg a.i/ha with 1 hoeing at 45 days after ratoon initiation.

Sugarcane is one of the important cash crop of Assam occupying an area of about 29 thousand ha with an average productivity of 37 t/ha. Poor yield of the crop is mainly due to some abiotic and biotic stress conditions, social and technical constraints and poor mechanization. Major reasons for low yield are heavy monsoon rainfall, reduced sunshine hours, high incidence of insect pests, lack of irrigation and low input use. The crop is grown in almost all the districts of Assam under varied soil and climatic conditions. Major sugarcane growing districts are Karbi-Angolong, Nagaon, Dima Hasao, Sonitpur and Golaghat. Almost all the cane produced in the state is utilized for making of jaggery except in places near city areas where the cane is used for raw juice during summer season. However, cane growers earn less income due to lack of adequate market facility and absence of proper marketing channel. The state has tremendous scope of enhancing the cane productivity through development of high yielding and pest and disease resistant varieties, development of abiotic and biotic stress management modules, adopting integrated nutrient supply system and sustaining its productivity by following suitable cropping systems.

A promising midlate maturing sugarcane variety, CoBln 04174 was developed at Sugarcane Research Station, Buralikson, Assam from the general collection of C 79180 through clonal selection. The variety was tested in the AICRP trial under different discipline and on farm trials of different agro climatic zones of Assam. The variety CoBln 04174 recorded an average cane yield of 65.54t/ha and sugar yield of 7.63 t/ha with an improvement of 4.58% for cane yield and 3.52% CCS yield over the best standard CoSe 92423 across the centres in two plant crop and one ratoon crop. Besides this, the variety CoBln 04174 recorded average cane yield of 70.4 t/ha which is 22.26% higher over the best standard CoP 9301 (57.58t/ha) in the trials conducted at Sugarcane Research Station, Buralikson. The variety was moderately susceptible to red rot but moderately resistant to borer insect of sugarcane. The variety CoBln 04174 has been identified for release in North Eastern Zone.