{"title":"Falling of asparagus flowers (Asparagus officinalis Linneo.) for the handling of Prodiplosis longifila Gagné in the irrigation of the Chavimochic project","authors":"S. Prado, J. Castillo, S. Rodríguez","doi":"10.21704/PJA.V2I1.1198","DOIUrl":"https://doi.org/10.21704/PJA.V2I1.1198","url":null,"abstract":"The asparagus, a dioecious plant, usually includes plants of both sexes, though also hermaphrodite ones. The male inflorescences are frequented by adult Prodiplosis longifila, who lay such large amounts of eggs on them that its populations can reach millions of individuals over a lapse of 20 to 30 days, which is the plant regular flowering period. The field investigation took place in two locations: (i) the Irrigation Research Unit of the Universidad Nacional Agraria La Molina (UNALM) and (ii) properties of the Agricultural Society of Viru (SAVSA). The number of fallen flowers and larvae per bud after applying multiple treatments on asparagus plots of the two locations was counted to determine the best concentration and application time of various fertilizers to induce the highest percentage of flower fall to manage P. longifila populations. In the UNALM the fertilizer B Dose 2 generated the highest percentage of fallen flowers, 82.1 % ± 14.85 %, and the fertilizer C Dose 1 caused 74.94 % ± 13.78 %. In SAVSA the fertilizer B Dose 3 made a percentage of fallen flowers of 50.6 % ± 21.56 % and fertilizer B Dose 2, 49.85 % ± 16.28 %. The average number of P. longifila 2nd-stage larvae, evaluated on fifteen flowers and in three moments was 3.9 larvae. Foliar fertilizers applications affected both male and female flowers almost equally in all treatments, percentage-wise. Foliar fertilizers promote asparagus flowers falling, consequently contribute to a significative reduction of P. longifila populations, due to a larvae exposition to rapid desiccation under the sun.","PeriodicalId":283246,"journal":{"name":"Peruvian Journal of Agronomy","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128587995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Santistevan, R. Borjas, L. Alvarado, V. Anzules, V. Castro, A. Julca
{"title":"Sustainability of lemon (Citrus aurantifolia Swingle) farms in the province of Santa Elena, Ecuador","authors":"M. Santistevan, R. Borjas, L. Alvarado, V. Anzules, V. Castro, A. Julca","doi":"10.21704/PJA.V2I3.1210","DOIUrl":"https://doi.org/10.21704/PJA.V2I3.1210","url":null,"abstract":"Surveys were applied to a sample of 83 lemon producers from this province, with structured questions about economic, ecological and socio-cultural dimensions. The sustainability was determined with techniques of multicriteria analysis to calculate the Economic Indicator (IK), Ecological Indicator (IE) and Socio-Cultural Indicator (ISC), to estimate the General Sustainability Indicator (IS Gen) of each farm. The 25.3% of the farms had an IK> 2; 60.24% an IE> 2 and 55.4% an ISC> 2. The 74.7% of the farms had an IS Gen <2, which indicates that the farms are not sustainable.","PeriodicalId":283246,"journal":{"name":"Peruvian Journal of Agronomy","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130211823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Maraví, O. Buendia, L. Alvarado, R. Borjas, V. Castro, A. Julca
{"title":"Characterization of banana farms (Musa spp.) in Cuyani Microbasin, Pichanaki District, Chanchamayo Province (Junín, Perú)","authors":"J. Maraví, O. Buendia, L. Alvarado, R. Borjas, V. Castro, A. Julca","doi":"10.21704/PJA.V2I2.1200","DOIUrl":"https://doi.org/10.21704/PJA.V2I2.1200","url":null,"abstract":"The objective of this study was to characterize banana farms in the Cuyani Microbasin in the district of Pichanaki, Chanchamayo province (Junin, Peru). We worked with a producer organization that has 400 partners, of which a sample was taken (n = 80) using the proportions method. It was found that the banana farms are very diverse, the person in charge is mostly a man, but there is an interesting percentage of the female gender in the administration of the farms. In general, producers have a basic educational level. The production system is traditional, the banana is grown alone or associated with other crops, such as coffee. Most producers consider that pests and diseases are the main factors limiting production, since they reduce yields and increase production costs. The farms were classified in five groups, the most important of which was 45% of the farms whose owner is a male, between 44 and 56 years old, with secondary education, who lives on the same farm. They do not have a property title, the house does not have basic services, and they have poultry and guinea pigs. They have 2 to 3 hectares of banana (cultivars: Island and Palillo, 600 to 1000 plants/ha). Its production costs are between 2000 and 3600 soles and a yield of 6.5 to 7.5 t/ha. The cultivar Isla is the most common but also the cultivars Palillo, Morado and Biscocho are planted.","PeriodicalId":283246,"journal":{"name":"Peruvian Journal of Agronomy","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114186525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Morphological and molecular identification of Phytophthora cinnamomi Rands as causal agent of Crown and root rot in Blueberry (Vaccinium corymbosum) in Peru","authors":"M. Huarhua, J. Flores, R. Acuña, W. Apaza","doi":"10.21704/PJA.V2I2.1202","DOIUrl":"https://doi.org/10.21704/PJA.V2I2.1202","url":null,"abstract":"The Blueberry production in Peru has had rapid growth in the last five years, from having no area of more than 3050 hectares at present. As a result of this increase, many pathologic plant problems have appeared among them Phytophthora sp. causing plants with symptoms of wilt, reddish of lower leaves, regressive death, rotting of roots and crown of different production areas of Peru. However, there is no identification reported in Peru. Therefore, this study was conducted in the Plant Pathology Clinic of the Universidad Nacional Agraria La Molina with the objective of to identify the species of Phytophthora causing Crown and root rot isolated from blueberry in Peru. Four isolates from the blueberry´s field were identified by morphological, molecular and pathogenically features. All the isolates formed corralled-type colonies with hyphal swelling on PDA and V-8 agar and produced obpyriform or ellipsoidal sporangia and globes chlamydospores. The internal transcribed spacer (ITS) of rDNA was amplified and sequenced with primer ITS1/ITS4 to confirm the identification, All the ITS nucleotide sequences from isolated obtained were submitted at GenBank of NCBI (Number Accession MH777152 to isolate AR-1, MH777151 to isolate AR-2, MH777150 to isolate AR-4, and MH777149 to isolate AR-3). Each one of the sequences showed 100% of homology with sequences of reference of P. cinnamomi in GenBank. Pathogenicity tests showed symptoms of redness and yellowing and root and Crown rot on Blueberry cv. Biloxi after 30 days of inoculation. Finally, concluded that P. cinnamomi is the species causing Crown and root rot in Blueberry in Peru. To our knowledge, this is the first report of P. cinnamomi on blueberry in Peru.","PeriodicalId":283246,"journal":{"name":"Peruvian Journal of Agronomy","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131920725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Callohuari, Clorinda E. Vergara, Jorge E. Jiménez
{"title":"Insect pests associated with Andean lupin (Lupinus mutabilis Sweet) and their parasitoids in Peruvian central coast – (Lima, La Molina)","authors":"Y. Callohuari, Clorinda E. Vergara, Jorge E. Jiménez","doi":"10.21704/PJA.V2I2.1199","DOIUrl":"https://doi.org/10.21704/PJA.V2I2.1199","url":null,"abstract":"This survey aimed to determine the insect pests associated with Andean lupin ( Lupinus mutabilis Sweet) and its parasitoids, under Peruvian central coast conditions. Sampling was made every seven days with the following methods: linear meter evaluations, plant organ evaluations, pitfall traps, and beating trays. Infested plant organs were taken to the laboratory for adult insect recovery (phytophagous or parasitoids). Pitfall traps and beating tray samples were also processed and stored. During the survey, 14,051 individuals belonging to 11 orders and 91 families were recorded. Insects that infested Andean lupin were Melanagromyza lini Spencer (stem borer), Liriomyza huidobrensis (Blanchard) (leafminer), Crocidosema aporema (Walsingham) (budborer), Grammopsoides tenuicornis (Casey) (stem borer) and Frankliniella occidentalis (Pergande) (bud and flower thrips). Diglyphus websteri (Crawford), D. begini (Ashmead), Chrysocharis flacilla (Walker), C. caribea Boucek, Chrysocharis sp. and Halticoptera arduine (Walker) were recorded as parasitoids of L. huidobrensis , whereas Carcelia sp. was recorded for C. aporema .","PeriodicalId":283246,"journal":{"name":"Peruvian Journal of Agronomy","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125439698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Application of nitrogen fertilizer in maize in Southern Asia: a review","authors":"Jiban Shrestha, A. Chaudhary, D. Pokhrel","doi":"10.21704/PJA.V2I2.1201","DOIUrl":"https://doi.org/10.21704/PJA.V2I2.1201","url":null,"abstract":"The rate, time and method of nitrogen (N) fertilizer application are strongly related to growth, development, and yield of the crop. This study principally focuses on the role of the nitrogen in growth, development, and production of the maize, emphasizing time and methods of fertilizer application and their suitable rates. The review shows that crop yield increases up to certain limit and declines if applied in an excess amount of nitrogen. Nitrogen affects various physiological and biochemical processes in plant cells that ultimately affect the growth and development of the plant. Nitrogen response by maize differs due to growth stages, environment and genotype of maize. Hybrid and improved maize varieties are more nitrogen-responsive than local varieties of maize. Proper nitrogen applications as basal doses at planting stage, split doses at critical growth stages namely knee high, and flowering stages are necessary for higher grain yield. This review serves as a useful tool to maize researchers and growers for making the right decision on nitrogen application on maize.","PeriodicalId":283246,"journal":{"name":"Peruvian Journal of Agronomy","volume":"95 4-6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114009129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. F. Pommpelli, J. M. Figueiroa, Flavio Lozano-Isla
{"title":"Allometric models for non-destructive leaf area estimation in Eugenia uniflora (L.)","authors":"M. F. Pommpelli, J. M. Figueiroa, Flavio Lozano-Isla","doi":"10.21704/PJA.V2I2.1133","DOIUrl":"https://doi.org/10.21704/PJA.V2I2.1133","url":null,"abstract":"We aimed to propose a reliable and accurate model using non-destructive measurements of leaf length (L) and/or width (W) for estimating leaf area (LA) of Surinam cherry ( Eugenia uniflora L.). For model construction, 560 leaves were randomly sampled from different levels of the tree canopies and encompassed the full spectrum of measurable leaf sizes. Power models better fit E. uniflora leaf area than linear models; but, among of then, the best fit were made when product of the L and W (LW) were used. To validate these models, independent data set of 156 leaves were used. Thus, we developed a single power model (Yi = β0 xβ1) [LA = 0.685 (LW)0.989; standard errors: β0 = 0.014, β1 = 0.005; R2 a = 0.997] with high precision and accuracy, random dispersal pattern of residuals and unbiased. A simpler linear model [LA = 0.094 + (LW * 0.655); standard errors: β0 = 0.025, β 1 = 0.001; R2 a = 0.998] also described here to estimate leaf area of E. uniflora, which are as good as the first. The simplicity of the latter model may be relevant in field studies, as it does not demand high precision or expensive instruments.","PeriodicalId":283246,"journal":{"name":"Peruvian Journal of Agronomy","volume":"220 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133908975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}