Weaver ants can boost cashew yield, study shows




By Jimoh Babatunde with agency reports

THE cashew (Anacardium occidentale) was introduced from Brazil in the 16th century and has become an economically important cash crop for a number of African countries. In the Benin Republic, for instance, raw cashew nuts have replaced cotton as the number one agricultural export produce and account for over 13% of export earnings.
Production is, however, severely constrained by infestation by several insect pests, sap-sucking insects, leaf miners, branch borers, coreid bugs, mirid bugs, and thrips, which adversely affect the quality of harvestable nuts and causes yield losses of up to 80%.
In a recent report published in the Journal of Agricultural and Forest Entomology, a team of researchers that includes Dr Jean-François Vayssières, IITA entomologist, present remarkable findings.
Cashew nut yields can be boosted by as much as 78% with weaver ants only, and 151% with ants and GF-120 bait sprays, when treatments incorporating the African weaver ant (Oecophylla longinoda) are employed against Béninois insect cashew pests. The researchers carried out their two-year study on a cashew orchard in the Parakou area of Bénin. First they divided the cashew trees into three blocks. Each block was then divided into four treatments, each with 72 trees.
Sugar solution
The treatments were as follows: a plot of trees colonized by weaver ants (ants); a plot of trees colonized by weaver ants fed with sugar solution (ant feeding); and an integrated pest management system (IPM) consisting of a plot of trees colonized by weaver ants and with spot application of GF-120. GF-120 is a biopesticide mixed with protein bait compatible with organic production but detrimental to cashew pests. Finally, the control treatment against which the performance of the other treatments was measured consisted of a plot of trees not subjected to any form of pest control.
Trees protected by weaver ants were compared with those without any form of protection. They found that nut yield and weight increased by 78% and 73% for the ants treatment, by 122% and 118% for the ant feeding treatment, and by 151% and 141% for the IPM treatment compared with the control. “The presence of weaver ants patrolling the trees provides protection against pests,” said Dr Vayssières. “They can have a direct impact by capturing insect pests such as cashew bugs and also provide, ‘visual and olfactory cues’ that act as a repellent.”
The efficacy of weaver ants as natural biocontrol agents against a wide range of pests as shown by this study is in harmony with findings from previous studies carried out by Dr Vayssières in 2008. These demonstrated that Oecophylla Ionginoda was efficient in repelling and reducing damage caused by these dangerous fruit flies—Bactrocera dorsalis, Ceratitis capitata, and Ceratitis cosyra—in mango and citrus plantations.
An unexpected finding from the present study, however, revealed that treatments using weaver ants and sugar-fed weaver ants led to an increase in thrips activity which resulted in a higher than expected reduction in nut quality. Conversely, when weaver ants were used in conjunction with GF-120, nut quality was enhanced and thrips damage reduced.
Therefore an IPM program incorporating weaver ants and GF-120 or a similar pesticide is recommended. Because organic pesticides are expensive, more studies are required to determine the cost effectiveness of this kind of program to ensure that the gains from an increased yield are not eroded by the costs of the treatments.
Dr Vayssières also confirmed that there are other control methods focused on thrips to be tested in this way. He added “The red ants, O. longinoda, are particularly suitable for African developing countries where fruit trees are rarely monitored for pests and where IPM is hampered by high tree size and inadequate/insufficient farmer knowledge.


- See more at: http://www.vanguardngr.com/2015/07/weaver-ants-can-boost-cashew-yield-study-shows/#sthash.e5DRe5St.dpuf

Comments

Post a Comment

Popular posts from this blog

Tomato disease outbreak: Institute appeals for research funding

The National Horticultural Research Institute, Ibadan, has appealed for funding to carry out research and create awareness on the tuta absoluta pest on tomatoes. The Institute’s Head of Vegetable Programme, Dr Olagorite Adetula, told the News Agency of Nigeria (NAN) in Ibadan on Friday that there was an urgent need to tackle the problem to save the economy. Adetula said the institute needed money to do surveillance survey of the pest/damage, ascertain the impact of the damage and proffer solution for eradicating the pest. She appealed to the Federal Government to help the institute get pheromones to lure and trap the pests and distribute to farmers. ``Spraying insecticides is not the best, the pest has high production rate, some of them can escape while spraying it and they will be resistant to the insecticide thereby causing us more cost. ``The pheromones can be used for six to eight weeks before changing it, it is very effective, the pest has short life cycle, wit
Read more

10,000 women farmers to be engaged in ECOWAS rice project – official

Image
 Mr Richard Olafare, the President, Seed Entrepreneurs Association of Nigeria (SEEDAN) says 10,000 women will be engaged in the recently inaugurated Rice Seed Up-Scaling Project. This is contained in a presentation on the project made available to the News Agency of Nigeria (NAN) in Abuja on Friday. Olafare said 8,000 youths would also be engaged in the scaling project. According to him, the number of women and youths represented 50 per cent and 40 per cent respectively of the 20,000 farmers that will participate in the project. NAN reports that the project is an initiative of the West Africa Seed Programme (WASP) in support of the ECOWAS Rice Offensive Programme that was inaugurated in 2014. Among other objectives, it is targeting the production of 60,000 metric tonnes of paddy rice for Nigeria by December 2017, using 1,200 certified seeds. The project is being implemented by SEEDAN in collaboration with the West and Central Africa Council for Agricultural Re
Read more

NEGPRO project can create more jobs with inclusion of meat production— Badmus

•Tuns Farm leads food safety, quality system audit The Chairman , Tuns Farms Nigeria, Asiwaju Olatunde Badmus, has disclosed that the proposed one million jobs expected to be created through the National Egg Production Scheme (NEGPRO) can be doubled if extended to meat production. He made this known when a team from the office of the Vice President, Federal Ministries of Agriculture, Health and Education at the company’s headquarters in Osogbo, the Osun state capital recently. Olatunde Badmus, while sharing the company’s experience on chicken inclusion in the Osun state’s school meal program which the company has been handling since the introduction of the school feeding program four years ago, said they can achieve so much more in terms of job creation through meat production “As we speak, six state governors among who are Kebbi and Borno, have signalled their government’s preparedness to look into this and have invited TUNS farm to their states to discuss modalities for
Read more