Adams I.P.,UK Environment Agency |
Miano D.W.,Kenya Agricultural Research Institute |
Kinyua Z.M.,Kenya Agricultural Research Institute |
Wangai A.,Kenya Agricultural Research Institute |
And 18 more authors.
The diagnosis of novel unidentified viral plant diseases can be problematic, as the conventional methods such as real-time PCR or ELISA may be too specific to a particular species or even strain of a virus, whilst alternatives such as electron microscopy (EM) or sap inoculation of indicator species do not usually give species level diagnosis. Next-generation sequencing (NGS) offers an alternative solution where sequence is generated in a non-specific fashion and identification is based on similarity searching against GenBank. The conventional and NGS techniques were applied to a damaging and apparently new disease of maize, which was first identified in Kenya in 2011. ELISA and TEM provided negative results, whilst inoculation of other cereal species identified the presence of an unidentified sap transmissible virus. RNA was purified from material showing symptoms and sequenced using a Roche 454 GS-FLX+. Database searching of the resulting sequence identified the presence of Maize chlorotic mottle virus and Sugarcane mosaic virus, a combination previously reported to cause maize lethal necrosis disease. Over 90% of both viral genome sequences were obtained, allowing strain characterization and the development of specific real-time PCR assays which were used to confirm the presence of the virus in material with symptoms from six different fields in two different regions of Kenya. The availability of these assays should aid the assessment of the disease and may be used for routine diagnosis. The work shows that next-generation sequencing is a valuable investigational technique for rapidly identifying potential disease-causing agents such as viruses. © 2012 The Authors Plant Pathology © 2012 BSPP. Source
Onyango O.C.,Kenya Plant Health Inspectorate Service
African Journal of Agricultural Research
With increasing human population against declining staple food crop yield trend, food insecurity is inevitable. Soil fertility problem has been identified as a major factor hindering maize productivity in Trans Nzoia district. Majority of these soils are acidic, deficient in nitrogen, phosphorus and at times other nutrient elements. A factorial experiment was laid out in randomised complete block design, with fertilizer option being main plot and variety as sub plot to explore better fertilizer treatments for maize production in Trans Nzoia. The treatments included three maize varieties and five fertilizer options. The maize varieties used were H.614D, H.6213, H.9401, while the fertilizer options included control (no fertilizer), farmyard manure (FYM) (one handful per hole), single super phosphate-SSP (188 kg/ha), diammonium phosphate-DAP (188 kg/ha) and DAP 125 kg/ha). There were significant yield differences among fertilizer treatments and among the varieties. DAP at 188 kg/ha and H.6213 gave the best mean yields of 10.19 and 9.62 kg a plot, respectively. SSP at 188 kg/ha and H 614 D treatments resulted in dismal crop yield performance of 8.03 and 8.46 kg a plot, respectively. Up to 23% yield can be lost in the field as rots especially with maize varieties exhibiting open cob tips. © 2010 Academic Journals. Source
Crawled News Article
NAIROBI (Thomson Reuters Foundation) - The first hybrid rice varieties developed in sub-Saharan Africa are yielding up to four times more than other improved varieties, say scientists, who are using web-based tools to identify the right climate conditions to maximise harvests. The 15 hybrids, bred in Kenya and Tanzania, are also tolerant to diseases and the high temperatures found in Kenya's western Lake Region and coastal areas. Local farmers have always depended on imported hybrid rice varieties, particularly from Asia, which sometimes do not adapt well to conditions in sub-Saharan Africa. As the climate shifts and arable land shrinks under population pressure, experts say there is a need for more innovative ways to produce food. Africa's food deficit is projected to increase to 60 million metric tonnes by 2020 if no action is taken, according to the Alliance for a Green Revolution in Africa (AGRA). Joe DeVries, director of an AGRA programme to strengthen Africa's seed systems, said productivity on the continent is limited by the fact that farmers have a narrow choice of improved varieties. “Most of them (are) planting varieties that were released more than 30 years ago,” he said. Denis Kyetere, executive director of the African Agricultural Technology Foundation (AATF), which has developed the new hybrids in a public-private partnership, said hybrid technology had revolutionised rice production in Asia, especially in China. Asia’s productivity dramatically increased from an average of 1.89 metric tonnes per hectare in 1949 to 6.71 tonnes per hectare in 2012. “With this technology, we look forward to Africa being able to feed Africa,” said Kayode Sanni, project manager for rice at the AATF. In 2014, Africa imported 12 million tonnes of rice, mostly from Asia, he noted. The AATF, in collaboration with private firm Hybrids East Africa Limited, has so far developed 140 hybrid rice varieties using African parent lines. Of these, 15 – each yielding 7 to 10 tonnes per hectare - have been presented to the Kenya Plant Health Inspectorate Service (KEPHIS) for national performance trials. U.S.-based aWhere Inc, a partner in the hybrid rice project, has developed web-based tools that allow scientists to determine when and where to conduct breeding, seed multiplication and seed production to take advantage of the best climate conditions. Improved inbred rice varieties, such as the New Rice for Africa (NERICA) lines, are already in use on African farms. With this method, two different parent varieties are cross-bred, and their offspring are selected through several cycles of self-pollination, or inbreeding, to get the desired result. The end product has the ability to reproduce itself through self-pollination because the rice plant flowers contain both the male and female organs. With hybrid varieties, the parent plants are crossed separately with new varieties, and the offspring from those crosses are united to produce a first-generation hybrid seed, which performs better than both parents. The process is repeated each time. Currently, the average yield of inbred rice varieties in sub-Saharan Africa is 2.3 tonnes per hectare. But in trials, some of the new hybrids have produced between 7 and 10 tonnes per hectare, said Sanni, more than the breeders had hoped for. “I think it is a tremendous breakthrough,” he added. One potential problem is that seeds harvested from hybrid plants are not recommended for replanting because their superior performance is lost due to genetic separation, resulting in a lower yield. That means farmers do not save seed from their harvest to plant again, and seed companies must cross the parent materials every season to produce new hybrid seed for planting. “This has always been a setback - particularly for farmers who cannot afford higher prices of hybrid seeds. But through this project, we have developed an innovative way of helping the poor farmers, so that they can borrow the seed and pay (it) back only after harvest,” said John Mann, managing director for Afritec Seeds Ltd, which is testing more than 100 hybrid varieties under the AATF’s “Breeding by Design” project. Although farmers will have to buy seeds each time they plant, the extra profit from the hybrids' higher yield is expected to be far higher than the cost of the seeds, said Sanni.
Crawled News Article
Many folks swear by Copernic’s Desktop Search application and it’s been around at least as long (if not longer) than either Google’s or Microsoft’s desktop search products. Somehow, I’ve missed the fact that Copernic offers a mobile client; not an app to search for information on your mobile device, but a mobile client that can remotely search your desktop PC for information. The only reason I caught wind of the product was that they just announced an iPhone-friendly version of the application. Looks like a great way to easily search for and retrieve information when you’re out and about, provided that you left your PC powered on. The mobile client is now in its second beta, so it’s not quite ready for prime time. You’ll also need either Windows Desktop Search or Copernic Desktop Search installed on your PC. There’s a list of FAQs on the mobile service right here, so check ’em out if this sounds as useful to you as it does to me.
Otieno W.,Kenya Plant Health Inspectorate Service |
Kigamwa J.N.,Kenya Plant Health Inspectorate Service
Sustaining market share and increasing market access for horticultural products require consistent compliance with official standards set by appropriate international treaties. The relevant treaties in this regard are the International Plant Protection Convention (IPPC) and Codex Alimentarius. Effective application of these standards consists of a highly functional and responsive export certification system on the supply side (exporting country) and a transparent import regulatory system on the demand side (importing country). This enables strict observance of the transparency provisions especially in regard to notifications, response to biosecurity enquiries and cooperation in information exchange. Despite many developing countries being contracting parties to the IPPC and Codex Alimentarius, the majority encounter difficulties in complying with standards set by these organizations. This is exemplified by frequent notifications on non-compliance with sanitary and phytosanitary (SPS) requirements of trading partners. Non compliance not only limits market access but also frequently results in loss of already established markets. Upsurge in cases of phytosanitary non-compliance due to some pests was experienced in 2007. Concerted efforts by Kenya's National Plant Protection Organization (NPPO), Kenya Plant Health Inspectorate Service (KEPHIS), collaborative actions of producers and exporters, quick information exchange among NPPOs, improved ability of the inspectors and scouts to identify the quarantine pests plus intensified pest management systems on the farms contributed to marked reduction of these cases of non-compliance. Strategic actions by KEPHIS and the industry resulted in development of an early warning system to improve responsiveness to emerging threats to the export market, a residue monitoring plan to manage issues on Maximum Residue Levels MRLs together with a targeted pest risk analysis and pest information management system. Source