Lower seed rates favor seed multiplication ratio with minimal impact on seed yield and quality

Field and laboratory studies were conducted in split plot design of three replications to determine effects of four sowing rates (50, 75, 100, 125 kg ha-1) and three row spacing (10, 20, 30 cm) on seed multiplication ratio, seed yield, and seed quality of wheat at Kulumsa and Assasa from 2012 to 2014. Results indicated that lower seed rates gave better seed multiplication ratio at both locations. Increasing seed rate from 50 to 125 kg ha-1 has increased seed yield at Assasa site from 3838 kg ha-1 to 4687 kg ha-1 though seed yield difference between seed rates of 75 and 125 kg ha-1 was statistically non-significant (p>0.05). Increasing seed rate from 50 to 100 kg ha-1 has continuously improved seed yield from 4171 to 4389 kg ha-1 at 20 cm row spaces at Kulumsa, but the difference was statistically non-significant. Laboratory studies indicated that seedling vigor index-II of seeds harvested from plots of 20 cm spacing and seed rate of 100 kg ha-1 have given highest value (1096.1 mg.%). In conclusion, seed rates as low as 50 kg ha-1 can be used at row space of 20 cm to accelerate early generation seed supply within the fast track variety release program in Ethiopia

Mortality of Sitophilus granarius (L.) and Rhyzopertha dominica (F.) Adults Exposed to Different Concentrations of Filter Cake in Stored Wheat

አህፅሮትየሲልከን ውሁድ ያሊቸው ግዑዝ ብናኞች የተከዘነ እህልን ከጎተራ ነፍሳት ከመከሊከል አንጻር ከኬሚካሎች ይልቅ ሇአካባቢ ተስማሚ ሇጤናም ጉልህ ጉዳት የማያስከትለ አማራጮች እየሆኑ መጥተዋል፡፡ ከዚህ ጋር ተያይዞ አንድ የሲሉከን ውሁድ ያሇው የማጣሪያ ኬክ ብናኝ በጎተራ ነፍሳት ሊይ የሚኖረውን የመቆጣጠር አቅም ሇመፈተሽ በጎተራ ነቀዝ እና በትንሹ እህል ቦርቧሪ ጥንዚዛ ሊይ ጥናት ተደርጓል፡፡ ጥናቱ የተከናወነው 1ኪ.ግ.፣ 0.75ኪ.ግ.፣ 0.5ኪ.ግ.፣ እና 0.25ኪ.ግ. የማጣሪያ ኬክ ብናኝ በአንድ ኩንታል ስንዴ ሊይ በመጨመር ሲሆን የብናኙን ውጤታማነት ሇመቆጣጠር ምንም ብናኝ ያልተደረገበት ስንዴ ከጎን ተጠንቷል፡፡ ጥናቱ ባጠቃሊይ ሇ14ቀናት የተከናወነ ሲሆን ብናኝ ባሇው ስንዴ ውስጥ የገቡ ጉልምስ ነፍሳት የደረሰባቸው የሞት መጠን ተገምግሟል፡፡ በዚህም መሠረት በጎተራ ነቀዞች ሊይ በሶስት ቀናት ብቻ ከ41.3% እስከ 70.0% የጉልምሶች ሞት የተከሰተ ሲሆን ይህ በትንሹ እህል ቦርቧሪ ጥንዚዛ ጉልምሶች ሊይ ከ73.3% እስከ 93.3% ሞት አስከትሏል፡፡ ከ14 ቀናት በኋሊ ሲታይ በጎተራ ነቀዝ ጉልምሶች ሊይ እስከ 98.7% ሞት ያስከተሇ ሲሆን በትንሹ እህል ቦርቧሪ ጥንዚዛ ሊይ ግን እስከ 100% ሞትን አስከትሏል፡፡ ስሇዚህ በዚህ ጥናት ሊይ የተካተቱ የነፍሳት ዝሪያዎችን በማጣሪያ ኬክ ብናኝ ከሞሊጎደል መቆጣጠር እንደሚቻል መመልከት ይቻሊል፡፡AbstractSilica based inert dusts are eco-friendly alternatives to control stored grain insect pests due to environmental and health concerns associated with use of synthetic insecticides. A study was conducted to determine the efficacy of filter cake (a silica-based inert dust) on the granary weevil, Sitophilus granarius (L.) and lesser grain borer, Rhyzopertha dominica (F.) in stored wheat. Filter cake dust of ≤0.4 mm particle size was admixed with 500 g of wheat seed to provide nominal rates of 10000, 7500, 5000, and 2500 ppm (mg/kg), while the control treatment consisted of wheat seeds that were untreated. The bioassays were carried out using a liter-sized plastic jars in completely randomized design with three replications. Experiments were maintained at 23.1±1.7oC and 61.0±4.3% relative humidity. Mortality data were collected at 3, 7, and 14 d after treatment. Results indicated that mean mortality rate at 3 d after treatment ranged from 41.3 to 70.0% in S. granarius and 73.3 to 93.3% in R. dominica. Mean mortality of S. granarius adults at 14 d in filter cake treatments was 84.0 to 98.7%, whereas that of R. dominica was 98.3 to 100%. The present results show that filter cake dusts can be used to control these two species in stored wheat. Filter cake has potential in protection of wheat from S. granarius and R. dominica infestations in storage

Major Insect Pests and their Associated Losses in Quantity and Quality of Farm-Stored Wheat Seed

አህጽሮትበተከዘነ ስንዴ ላይ በጎተራ ነፍሳት ሰበብ ጉልህ ብክነት ይደርስ ወይም አይደርስ እንደሆነ ብዙ ክርክር አሇ፡፡ የችግሩን አገር አቀፋዊ ይዘት ሇመረዳት ከአማራ፣ ከኦሮሚያ፣ ከደብብህ፣ እና ከትግራይ ክልሎች በተመረጡ አምስት የስንዴ አብቃይ ወረዳዎች ላይ የስንዴ ናሙናዎችን ከአርሶ አደር መጋዘኖች በመሰብሰብ የዳሰሳ ጥናት እ.አ.አ. በ2016 በሰኔ ወር ተከናውኗል፡፡ ከእናንዳንዱ አርሶ አደር ቤት አንድ ኪሎግራም በመውሰድ በድምሩ 150 ናሙናዎች ተሰብስበው ተፈትሸዋል፡፡ ከናሙናዎቹ ላይም የጎተራ ነፍሳት አይነቶች፣ በነፍሳት ምክንያት የደረሰ የክብደት መቀነስ በመቶኛ፣ በነፍሳት ምክንያት የደረሰ የመቦርቦር ችግር እና በመጨረሻም የዘር ብቅሇት ደረጃ መረጃዎች ተሰብስበው ተተንትነዋል፡፡ በተገኘው መረጃ መሰረት ከስድስት ያላነሱ የጎተራ ነፍሳት አይነቶች የታዩ ሲሆን በነፍሳት የተበሳ/የተቦረቦረ የስንዴ ፍሬ ቁጥር በየወረዳው በአማካይ በመቶኛ ከ3.6 እስከ 13.6 መሆኑ ታይቷል፡፡ በተመሳሳይ መልኩ በነፍሳት ምክንያት በዘር ላይ የደረሰ የክብደት መቀነስ በየወረዳው በአማካይ በመቶኛ 1.5 ነበር፡፡ በተጨማሪም አማካይ የዘር ብቅሇት በአማካይ በመቶኛ 72.3 ብቻ ሆኖ ታይቷል፡፡ በአሁኑ የዳሰሳ ጥናት ውጤት መሠረት በአርሶ አደሮች በተከዘነ የስንዴ ዘር ላይ በጎተራ ነፍሳት ምክንያት የሚደርሰው ጉዳት በዓይነትም በጥራትም ረገድ ከተጠበቀው በላይ መሆኑን ሇመረዳት ይቻላል፡፡ ስሇዚህም አግባብነት ያላቸው የተከዘነ ስንዴ መጠበቂያ አሰራሮች ሇአርሶ አደሮች መተዋወቅና በክዘና ደረጃ የሚደርሰውን ብክነት የመቀነስ ሥራ መሠራት አሇበት፡፡AbstractThere is considerable debate over the importance of losses associated with insect pests of stored wheat at the farm level in Ethiopia. A survey was conducted to assess the most significant insects and losses of farm-stored wheat in five districts in Amhara, Oromiya, Southern Nations, Nationalities and Peoples, and Tigray regional states of Ethiopia during 2016. One kg samples of stored wheat seed were collected over a period of eight months from 150 farmers. The samples were kept in the laboratory for approximately six weeks to allow the population of insects present to develop and emerge as adults. After adult emergence, the resultant weight loss, seed damage, and loss of seed germination were determined. Major primary insect pests identified were the granary weevil, Sitophilus granarius, Sitophilus spp., and the Angoumois grain moth, Sitotroga cerealella. Secondary pests such as Tribolium spp., the India meal moth, Plodia interpunctella, and Liposcelis spp. were detected in a few samples. Wheat experienced mean percentage kernel damage that ranged from 3.6 to 13.6%. Mean weight loss due to insects was 1.5%, while mean seed germination was only 72.3%. The present survey indicated that farmers are incurring a considerable loss in the quantity and quality of stored wheat due to insects. Hence, there is an urgent need to devise appropriate tactics for protecting the losses in farm-stored wheat in Ethiopia

Occurrence of Mycotoxins in Stored Maize in Ethiopia

አህጽሮትበእህል ላይ በሚከሰቱ ሻጋታዎች ምክንያት የሚፈጠሩ መርዛማ ኬሚካሎች ሇምግብ ደህንነት፣ ሇምግብ አቅርቦትና ሇድንበር ተሻጋሪ የንግድ ሥርዓት ስጋት በመሆናቸው አሇምአቀፍ ትኩረት እየሳቡ ይገኛለ፡፡ በአገራችን የበቆሎ ምርት ላይ ያሇውን የእነዚህ መርዛማ ኬሚካሎች ክስተት ሇማጥናት ከአምስት የበቆሎ አምራች ወረዳዎች ከተውጣጡ አርሶ አደሮች ቤቶች የተሰበሰቡ 150 ናሙናዎች ላይ ፍተሻ ተደርጓል፡፡ በጥናቱ አራት ዓይነት ሻጋታ ወሇድ መርዛማ ኬሚካሎች የተገኙ ሲሆን ከእነዚህ ውስጥ አፍላቶክሲን የተባሇው መርዛማ ኬሚካል መጠኑ ቢሇያይም በሁለም ናሙናዎች ላይ ተገኝቷል፡፡ ስሇሆነም የእነዚህን ሻጋታ ወሇድ መርዛማ ኬሚካሎች ክስተት ሇመከላከል በአርሶ አደሮች ደረጃ አስፈላጊው የድህረ ምርት ክብካቤ እርምጃ መወሰድ አሇበት፡፡AbstractMycotoxins are attracting worldwide attention because of their implications for food safety, food availability, and international trading. A study was conducted to determine mycotoxin occurrences in stored maize in 150 samples collected from five major maize growing districts of Ethiopia: namely, Mer-Awi, Wenberma, Chelia, Halaba, and Toke Kutaye. Total aflatoxins (AFT), total fumonisins (FUM) and deoxynivalenol (DON) were measured using lateral flow immunoassay whereas the Enzyme-Linked Immunosorbent Assay was used for ochratoxin A (OTA). Results indicated that incidences of AFT, FUM, OTA, and DON were 100, 32.7, 24, and 7%, respectively (N=150). The average level of AFT was 14.7±11.6 ng/g ranging between 6.3 ng/g to 150 ng/g. Incidences of safe levels of AFT were 94.6%, 11.3%, and 0% when evaluated by the maximum tolerable level (MTL) of Food and Drug Administration (FDA), East African Community (EAC), and the European Commission, respectively. The average level of FUM in positive samples was 0.68±0.94 μg/g with a range between 0.2 μg/g and 6.52 μg/g. OTA positive samples had an average level of 8.2±30.6 ng/g and a range between 2 ng/g and 186.5 ng/g. Likewise, the average and range of DON in positive samples were 0.65±0.46 μg/g and 0.27−1.98 μg/g, respectively. Co-occurrences of mycotoxins were observed, and AFT-FUM co-occurrence incidence was the highest of all others (32.7%, N=150). The occurrence of mycotoxins in stored maize in Ethiopia is evident from the survey result

Comparison of hermetic bags with polyethylene‐lined polypropylene bags for prolonged storage of faba bean (Vicia faba L.) seeds in Ethiopia

Abstract Poor storage facilities expose seeds to deterioration, resulting in low seed quality under a prolonged storage time. We compared the performance of five bag types: Two hermetic bags (Super GrainPro bag [SGB] and Purdue Improved Crop Storage bag [PICS]), with three non‐hermetic bags (woven polypropylene bag lined with polyethylene [WPP lined with PE], polypropylene bags [PP], and jute bags) for the storage of faba bean seeds for 24 months. Faba bean seed quality was assessed under ambient conditions after 0, 6, 12, 18, and 24 months of storage. Parameters investigated include seed moisture content, thousand seed weight, germination percentages, vigor index I and II, speed of germination, percentage of insect‐damaged seed, and insect counts. Results indicated that there was a significant (P ≤ 0.01) interaction of bag types and duration for all tested parameters. Hermetic bags and WPP lined with PE maintained germination percentage above 90% during 12 months of storage. The vigor index remained above 1600 mg% for hermetic bags and WPP lined with PE during 12 months of storage. However, non‐hermetic bags exhibited a rapid drop in vigor index beginning from 6 months of storage. Hermetic bags and WPP lined with PE allowed minimal insect breeding and hence decreased the seed damage caused by insects. The present results demonstrated that in addition to the PICS bags and SGB, the WPP lined with PE can be used for short‐period storage for up to 12 months without incurring a significant loss of seed quality. Hence, we recommend the introduction of WPP lined with PE as faba bean seed storage technique under conditions where hermetic bags are inaccessible to resource‐poor farmers