Abstract
The main review purpose this paper provides updated information on the effect of different transplanting dates on the infestation of tobacco insect pets were carried out at different location by different Scholars. The results revealed that different trials conducted in different agro ecological zone indicated that damage was higher and green leaves yield decrease were in late transplanted tobacco. While, the damage was gradually decrease and green leaves yield increase in early transplanted tobacco. Numerous species of insect pests of tobacco affect the crop in the field, in the greenhouse, and in storage. The effect tobacco insect pests reduced green leaf yield, quality and damage roots, leaves, buds parts of plants and others transmit several important tobacco disease pathogens. As management systems for flue-cured tobacco (Nicotiana tabacum L.) used different transplanting date were compared to evaluate their influence on insect pestsâ damage, leaves yield and quality of flue-cured tobacco. The results indicated that early transplanted significantly increase leaf yield, growth parameters and decrease insect pest damage incidence. The study indicated that transplanted has pronounced positive effect on management of tobacco insect pests and growth of tobacco.
Introduction
The tobacco plant is native to South America. It is currently grown in many tropical and subtropical areas of the world. Tobacco is an herbaceous annual or perennial plant in the family Solanaceae. The crop has a thick, hairy stem and large, simple leaves which are oval in shape, produces white, cream, pink or red flowers which grow in large clusters. Tobacco grow in deep, well-drained loamy soils with little or no risk of flooding [1].
Several biotic and abiotic factors limit tobacco leaf yields. They include adverse climate, soils, insects, diseases, weeds, rodents etc. Tobacco is attacked by many insect pests both in nursery and main field. These pests caused considerable damage to seedlings in the nursery and leaf in the transplanted crop reducing yield and quality of crop. The major pests that infest tobacco in the nursery and field are: leaf eating caterpillar, Spodoptera litura; whitefly, Bemisia tabaci; stem borer, Scrobipalpa heliopa in the nursery and in the field infested by ground beetles, Mesomorphus villiger; tobacco bud worm, Helicoverpa armigera and tobacco aphid, Myzusnicotianae. Moreover, cigarette beetle, Lasioderma serricorne is a pest of stored tobacco. Apart from these, minor pests like ants, mole crickets and rove beetles, earthworms and grasshoppers occur in the nursery, and stink bug, Nazara viridula occurs in the field crop. It is roughly estimated that about 34% loss of cured leaf can be avoided by adopting appropriate pest management practices [2-3].
Tobacco is one of important agriculture crop, in Ethiopia, with social and economic importance and grown for commercial purposes by state-owned farms and farmers around those farms. Green leaves produced by small-scale farmers yield and quality remains low due to different constraints. Among constraints, transplanting time is an important factor which affect yield and growth of crop. Therefore, adjusting time of transplanting dates an essential cultural management practice that increase yield and quality leaves of tobacco [4,5 &6]
Researches results conducted on effect of transplanted time indicted that adjusting time of transplanting often helps tobacco crop to escape from infestation of insect pests and to harvest highest green leaves yields [7]. The integrated pest management (IPM) system is important in combining cultural, natural, and chemical controls in order to maintain insect pest population and promote the use of insecticides only when necessary [8]. Hence, keeping the above concept in view, therefore, in this review attempted made to evaluate the effectiveness of different transplanting dates for the management of tobacco in different region.
Materials And Methods
As a methodology different journal articles used to review from these peer reviewed data. Through searching results 15 papers were retrieved and by reading abstract, key work and conclusion parts of these paper were identified that meet the objective of this report.
Research Result Review on Effect of Different Transplanting Dates for Control of Tobacco Pests
Tobacco is attacked by variety of soil, foliar, and stored tobacco insect pests can attack tobacco from transplant through harvest through the grown period [9]. Aphid cause indirect losses; their feeding reduces plant vigor, they may spread viruses, and sooty mold produced when large populations of aphids are present reduces tobacco quality; flea beetles cause stress when feeding on young plants and directly damage harvestable leaf when feeding on mature plants; and hornworms and budworms causes direct losses by feeding direct on plant leaves.
Tobacco insect pests are active at predictable times during the growing season flea beetle infested tobacco 1 weeks after transplanted until harvest; Horn worms started 3 weeks after transplanted until topping; Aphid and bud worms at 3 weeks after transplanted and cut worms 1-4 weeks after transplanted. Timely field checks and use of treatment guidelines will allow early detection and assessment of problems, so sound pest management decisions can be made [10].
Cultural control methods involve of utilizing alternative crop rotation, proper sanitation of fields, tillage, trap cropping, alternative planting dates, and host plant resistance to limit damage to crops or reduce pest population [11]. [12] conducted field trial in 1987-1989 to study the influence of transplanting dates on tobacco budworms threshold density indicated that tobacco budworms population density of less than one per 20 plants in the early transplanted tobacco (late march) while late transplanted (late April) tobacco budworms threshold levels (1,2,4, or 8) budworms per 20 plants significantly affected affect tobacco quality, yield and budworm damage.
Date of planting is one of the crop habitat diversifica tions that are to be looked into, to minimize the incid ence of insect pests on tobacco so that its can be en hanced yield. Late- planted tobacco is also at greater risk from leaf diseases such as brown spot caused by Alternaria, weather damage, and damage from insects such as budworms and aphids [13]. Besides late transplanted tobacco caused more rapid growth, hasten floral initiation, produce thinner leaves, and possibly hasten senescence and reduce yields [14].
Aphid abundance was significantly lower in transplanting tobacco 10 days after garlic transplantation at a density of 5.85 individual plants per square meter than in the other treatments that showed experiment conducted in Liancheng County in Longyan City, Fujian Province, in China in 2014 and 2015 by [15].
Conclusion
The review articles concluded that the need for demonstrations on the use early transplanting dates of effective insect pests control methods, and all found effective in management of pests in agriculture they need to be validated scientifically
Acknowledgement
This review article contains information gathered from numerous published resources, and thus I would like to extend our appreciation to all authors of the references used in this manuscript
