Effect of different grafted tomato rootstocks on damage of leafminer, Liriomyza sp.

عنوان دوره: دومین کنگره بین المللی حشره شناسی ایران
نویسندگان
چکیده
Grafting is a technique by which two or more plants are joined, forming a single plant. One of the main purposes of grafting in vegetable crops is to induce resistance to pests and diseases. Liriomyza spp. (Dip.: Agromyzidae) is an economic pest on vegetables such as tomato (Solanum lycopersicum L.). Chemical control of these leafminers has always been difficult, due to various reasons. So other control methods must be considered. The experiment was conducted in a randomized complete block design with 7 treatments and 4 replications in the research greenhouse of Isfahan Agricultural and Natural Resources Research and Education Center (Isfahan, Iran). The treatments were as follows: grafted Maxifort rootstock (GMR), grafted Newton rootstock (GNR), grafted Kingkong rootstock (GKR), rooted cutting of Maxifort (RCM), rooted cutting of Newton (RCN), transplanting of Newton (TN) and direct seeding of Newton (DSN). Rootstocks (all by Newton, prevalent tomato variety, as scion), cuttings (rooted in the laboratory) and transplants were planted in the greenhouse in rows, so that each plot contained 5 plants. Sampling was carried out on two middle plants in each plot. For this purpose, infestation percentage (infested leaves/ plant) was determined. However, due to differences in the number and extent of larval mines in the infected leaves, damage rating (based on a 10-degree scale) and cumulative numbers of mines were recorded using a stratified random sampling on six true leaves of the selected plants. Data were transformed and then analyzed. Results showed significant differences among treatments for all three variables. For infestation percentage, RCM had significantly the lowest mean (58.14%/ plant). The other treatments were placed in a separate group, in which the highest and lowest means belonged to TN and GMR (82.53 and 74.33 %/ plant, respectively). For cumulative number of mines, treatments were placed into three groups. TN and GNR with highest means in one group (5.33 and 4.16 mine/ true leaf, respectively), and CRM with the lowest mean (2.4 mine/ true leaf) in another group. Other treatments were placed in an intermediate group. There was no significant difference among treatments for damage rating, while the highest and lowest means were belonged to TN and CRM (4.00 and 3.43/ plant, respectively). Overall, the damage of Liromyza leafminers was lower on Maxifort rootstock and plants grafted on this rootstock. The effect of these rootstocks on the major pests and diseases of greenhouse tomatoes must be studied in future.
کلیدواژه ها