Peanut Science最新文献

{"title":"Comparison of Trimble GreenSeeker and Crop Circle (Model ACS-210) Reflectance Meters for Assessment of Severity of Late Leaf Spot","authors":"B. Jordan, W. D. Branch, A. Coffin, C. M. Smith, A. Culbreath","doi":"10.3146/ps18-19.1","DOIUrl":"https://doi.org/10.3146/ps18-19.1","url":null,"abstract":"Four field experiments conducted in 2015 were used to examine the relationships among normalized difference vegetation index (NDVI) measurements from two canopy crop sensors and visual estimates of defoliation by late leaf spot (Nothopassalora personata) of peanut (Arachis hypogaea) the predominant foliar disease in this study. For each evaluation, reflectance was measured with each the two meters, and leaf spot severity was measured visually within as short a time as possible. Linear and quadratic regression models were used to characterize the relationships between percent defoliation from late leaf spot and NDVI measured with the GreenSeeker (NDVIGS) and Crop Circle (NDVICC) instruments and the relationships between NDVIGS and NDVICC. NDVIGS decreased with increasing percent defoliation according to linear or quadratic functions in three of the four trials, NDVICC decreased with increasing percent defoliation according to linear functions in three of four trials. In two of the four trials, NDVICC increased with increasing NDVIGS according to quadratic functions, but there was no significant regression for those variables in two trials. In three of the four trials, NDVICC linear regression had a better fit for predicting percent defoliation according to the coefficient of determination (R2). There was no indication for either instrument that the same NDVI reading corresponded with the same level of defoliation across trials. Results indicated that NDVI measurements from the two instruments are not interchangeable.","PeriodicalId":19823,"journal":{"name":"Peanut Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87828834","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":"Naturally and Artificially Drought-Induced Small-Plants within the Pure-Line Runner-Type Peanut Cultivar ‘Georgia-10T’","authors":"W. D. Branch, C. Kvien, A. Culbreath","doi":"10.3146/ps19-1.1","DOIUrl":"https://doi.org/10.3146/ps19-1.1","url":null,"abstract":"\u0000 During 2011 at Tifton and Plains, GA, there was an early-season drought stress period during May and June. A few drought-tolerant plants were identified and tagged which appeared green and turgid amongst otherwise dry and severely-wilted plants within the pure-line, runner-type peanut (Arachis hypogaea L.) cultivar, ‘Georgia-10T'. Pod and seeds were harvested from these drought-tolerant individual plant selections (IPS) for increase and testing. During autumn and winter of 2014 to 2015, a greenhouse drought study was utilized to test these IPS's compared to the parental check cultivar. Green and turgid plants were identified within the same check cultivar after exposing the plants to an early-season two-wk drought stress period at 60 and 90 d after planting. Seed from IPS of naturally occurring and artificially drought-induced plants produced similar normal and small-plants. Replicated preliminary yield tests were conducted during 2017 to compare progeny rows from these IPS's to the check cultivar, Georgia-10T. Field trial data indicated that the smaller-plants produced from early-season drought stress had significantly reduced yield, grade, pod size, and seed size as compared to larger plant selections and Georgia-10T parental cultivar. In a greenhouse study conducted during autumn and winter of 2017 to 2018, these small plants had significantly shorter internode length and mainstem height compared to the same small plants treated with gibberellic acid (GA3) which were taller and had longer internode lengths after one and two months. Small plants resulted from artificially and naturally occurring early-season drought-induced stress within the pure-line runner-type peanut cultivar, Georgia-10T, were caused by lack of GA3. The normal and small-plants each have bred true-to-type following several self-generations. The ramification of these findings suggest the importance of early-season irrigation, especially for seed production of peanut cultivars to avoid subsequent development of low-yielding, small-plants induced by drought-stress.","PeriodicalId":19823,"journal":{"name":"Peanut Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88643226","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":"Foliar Fertilization as a Strategy to Increase the Proportion of Mature Pods in Peanut (Arachis hypogaea L.)","authors":"A. Pierre, M. Mulvaney, D. Rowland, B. Tillman, T. Grey, J. Iboyi, R. León, D. Perondi, C. Wood","doi":"10.3146/ps17-20.1","DOIUrl":"https://doi.org/10.3146/ps17-20.1","url":null,"abstract":"\u0000 Foliar application of nutrients is used by growers to remediate crop nutrient deficiencies, but anecdotal reports indicate there may be associated effects of accelerated crop maturity, particularly for irrigated peanut (Arachis hypogaea L.). Research was conducted to determine whether application of foliar fertilizers during early pod set could increase the proportion of early-maturing pods, and thereby increase the mature proportion of the profile under irrigated conditions. Field experiments were conducted in Florida at Citra in 2016, Jay in 2016 and 2017with a randomized complete block with four foliar fertilizer treatments, applied to GA-06G at R1 and again two wks later at R2. Treatments consisted of no foliar fertilizer (control), 10.0 kg N/ha, 1.0 kg P2O5/ha, and 0.34 kg B/ha at each application and two harvest timings. Harvest treatments were based on the adjusted growing degree d model for peanut and were timed to represent early and optimal crop maturity. Leaf tissue nutrient concentrations were determined from samples collected 24h after each foliar treatment application. Yield and proportion of mature pods were quantified after each digging date. Normalized difference vegetation index data showed no treatment differences. The maturity profile (percentage of mature pods present in the sample) was not consistently different from respective controls during either harvest period. Results indicate foliar fertilizer applied during flowering had little effect on maturity acceleration in peanut, though foliar fertilization may still be effective at alleviating in-season nutrient deficiencies. Within site-year, application of foliar fertilizer did not increase yield. Under sound soil fertility management programs, foliar fertilizers did not increase yield or the maturity profile of peanut.","PeriodicalId":19823,"journal":{"name":"Peanut Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87465074","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":"Effect of Calcium Source and Irrigation on Soil and Plant Cation Concentrations in Peanut (Arachis hypogaea L.)","authors":"K. D. Pegues, R. Tubbs, G. Harris, W. S. Monfort","doi":"10.3146/ps19-10.1","DOIUrl":"https://doi.org/10.3146/ps19-10.1","url":null,"abstract":"\u0000 Calcium improves seed formation and development of peanut kernels. Two primary sources of Ca fertilization in peanut are gypsum (CaSO4) and dolomitic lime (CaMg[CO3]2+CaCO3). Objectives of this research are to determine whether gypsum, lime, or application of both influences pH, extractable [Ca], [Mg], and [K] in the soil along with nutrient absorption, yield, and total sound mature kernels (TSMK) in peanut pods in irrigated compared to non-irrigated conditions. Experiments conducted in Tifton, GA in 2016 and 2017 evaluated Ca treatments with no supplemental Ca fertilizer, gypsum (330 kg Ca/ha) applied at first bloom, lime (897 kg Ca/ha) applied at planting, and lime (897 kg Ca/ha) applied at planting followed by gypsum (330 kg Ca/ha) applied at first bloom. Irrigating increased soil pH, [Ca] and [Mg] in pods, plus yield and TSMK of peanut. Irrigation also decreased [K] in pods, which was correlated with increased pod [Ca]. Soil pH and soil [Ca], [Mg], and [K] were influenced by fertilizer treatment, along with [Ca] and [Mg] in pods. Applications of lime increased pH and soil [Ca]. Lime also increased soil [Mg] when applied alone, but not when gypsum was also included. Application of gypsum reduced soil [Mg] when applied alone, but not when lime was included. The inclusion of both lime and gypsum reduced soil [K] compared to no application. These results display the competition of cations in soil. In peanut pods, using lime and gypsum increased [Ca] compared to no application, or only lime. However, when only gypsum was used, it reduced [Mg] in pods compared to a lime application or no fertilization. Although Ca fertilization did not affect yield, TSMK was greater when lime followed by gypsum were applied in sequence than where neither were applied in 2016. It is important to realize that applications of Ca can also influence concentrations of other cations important for growth. Peanut growers are encouraged to conduct soil tests to ensure soil [Mg] is not deficient or borderline before choosing to apply gypsum, and may require a supplemental Mg fertilizer if dolomitic lime was not applied.","PeriodicalId":19823,"journal":{"name":"Peanut Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91466944","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":"Inheritance of an Albino-Virescent Leaf Mutant in the Cultivated Peanut (Arachis hypogaea L.)","authors":"W. D. Branch, N. Brown","doi":"10.3146/ps19-3.1","DOIUrl":"https://doi.org/10.3146/ps19-3.1","url":null,"abstract":"\u0000 An Albino-Virescent Leaf mutant was recently found in an advanced Georgia peanut (Arachis hypogaea L.) breeding line, GA 082524. This breeding line was derived from the cross of ‘Georgia-02C' x (‘Georgia-01R' x ‘COAN'), none of which have exhibited any mutant phenotypes in the past. The Albino-Virescent leaf mutant was selected and reciprocal crosses made with GA 082524 to determine the inheritance of this unusual chlorophyll deficiency. F1 and F2 data indicated a single recessive gene, avl, controlled the Albino-Virescent leaf trait. Chi-square analysis indicated a good fit to the expected 3:1 segregation ratio. No maternal or cytoplasmic effects were detected among the progenies from reciprocal hybridization.","PeriodicalId":19823,"journal":{"name":"Peanut Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79522610","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":"Impact of First True Leaf Photosynthetic Efficiency on Peanut Plant Growth under Different Early-Season Temperature Conditions","authors":"Gurpreet Virk, C. Pilon, J. Snider","doi":"10.3146/ps19-8.1","DOIUrl":"https://doi.org/10.3146/ps19-8.1","url":null,"abstract":"\u0000 Selecting planting dates with optimal temperatures for plant growth and development is important for successful crop production. Photosynthetic rates of peanut leaves under adverse environmental conditions have been widely studied; however, characterization of photosynthetic efficiency of first true leaves as well as its contribution to plant growth is not well elucidated. The objectives of this research were to assess the influence of first true leaves of peanut cultivars on plant growth under different temperature conditions during early growth and at the onset of flowering and to identify the photosynthetic components more closely linked with photosynthetic efficiency of the first true leaves. Experiments were conducted with April (early), May (optimum), and June (late) planting dates in 2017 and 2018. Cultivars Georgia-06G, Georgia-14N, and TifNV-High O/L were evaluated. Measurements were taken at three and five wks after planting, early season and the onset of flowering, respectively. Rapid development of first true leaves of peanut plants contributed to whole-plant growth in the early season and at the onset of flowering across the temperature conditions. Net photosynthesis of first true leaves was not impacted by temperature conditions in the early season or at the onset of flowering primarily due to greater activity of non-stomatal components associated with the thylakoid reactions. Whole-plant growth was more considerably associated with first true leaf area development than photosynthetic efficiency of those leaves in peanut plants.","PeriodicalId":19823,"journal":{"name":"Peanut Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86977102","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":"Effects of insecticides applied in-furrow with superabsorbent polymer on peanut cultivars infected with Tomato spotted wilt virus","authors":"J. Haynes, N. Smith, A. Culbreath, K. Kirk, D. Anco","doi":"10.3146/ps19-7.1","DOIUrl":"https://doi.org/10.3146/ps19-7.1","url":null,"abstract":"\u0000 Spotted wilt of peanut (SWP) (Arachis hypogaea L.) caused by Tomato spotted wilt virus (TSWV; family Tospoviridae, genus Orthotospovirus) is a common disease that causes severe economic losses in peanut producing regions of the world. The causal agent is transmitted by thrips (Thysanoptera: Thripidae). Field experiments were conducted in 2017 and 2018 to determine if management of spotted wilt and subsequent productivity of peanut, including economic value, could benefit from applying a superabsorbent polymer (SAP) with standard in-furrow insecticides at planting. To determine this, two individual experiments were performed. In the first study, phorate and imidacloprid were individually applied with (2.24 kg/ha) or without SAP across cultivars susceptible (FloRun 157 or TUFRunner 511), moderately susceptible (Georgia 06G), and resistant (Sullivan or TifNV-High O/L) to TSWV. Nontreated controls were included in all experiments. The second study sought to determine the efficacy of different rates of SAP (0, 2.24, 5.6, and 8.97 kg/ha). The initial study was conducted in three locations across South Carolina and Georgia, while the second was conducted at Blackville, SC. In the first study, incidence of SWP was reduced (P = 0.0547) in multiple location-year analysis with a reduction of 9.4% observed in susceptible cultivars treated with phorate compared to untreated checks and those with imidacloprid. SAP did not affect final SWP incidence or economic value (P > 0.05) and was not consistently significant for yield. From the SAP rate study, a linear relationship of decreasing SWP incidence was observed with increasing SAP application rates for both imidacloprid and phorate in 2017 and 2018. On a means comparison basis, SWP was lower than the no-SAP check at SAP rates of 5.56 and 8.97 kg/ha, but this did not necessarily translate into increased yield. Additional experiments are needed to elucidate the relationship superabsorbent polymer may have to susceptible cultivars and phorate.","PeriodicalId":19823,"journal":{"name":"Peanut Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89236393","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":"Impact of Weed Management on Peanut Yield and Weed Populations the Following Year","authors":"Andrew T. Hare, D. Jordan, R. León, K. Edmisten, A. Post, D. J. Mahoney, D. Washburn","doi":"10.3146/ps19-9.1","DOIUrl":"https://doi.org/10.3146/ps19-9.1","url":null,"abstract":"\u0000 Field studies were conducted in 2016 and 2017 at two locations in North Carolina to evaluate common ragweed (Ambrosia artemiisifolia L.) (Lewiston-Woodville) and Palmer amaranth (Amanthus palmeri S. Wats) control (Rocky Mount), peanut (Arachis hypogaea L.) yield, and estimated economic return when herbicides were applied postemergence (POST) at 2 or 6 weeks after planting (WAP); 2 and 4 WAP; 4 and 6 WAP; and 2, 4, and 6 WAP. During the following growing season, cotton (Gossypium hirsutum L.) was planted directly into the same plots to determine the impact of weed management during the previous season on weed density. In absence of herbicides, peanut yield was 880 and 1110 kg/ha at Lewiston-Woodville and Rocky Mount, respectively. When weed control depended on a single herbicide application, yield ranged from 1760 to 2660 kg/ha at Lewiston-Woodville, and 2080 to 2480 kg/ha at Rocky Mount. When herbicides were applied twice, peanut yield ranged from 2690 to 3280 kg/ha at Lewiston-Woodville and 3420 to 3840 kg/ha at Rocky Mount. The greatest yields were recorded when herbicides were applied two or three times. Applying herbicides increased the estimated economic return of peanut compared to the non-treated control (NTC). In cotton the following year, common ragweed populations at Lewiston-Woodville were greater following the NTC or a single herbicide application 2 WAP compared to more intensive herbicide programs. Palmer amaranth density at Rocky Mount the following year in cotton was not affected by weed management the previous year in peanut. These results illustrate the relative importance of timing and duration of weed management for peanut and how they influence weed emergence in the following cotton rotational crop.","PeriodicalId":19823,"journal":{"name":"Peanut Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78006160","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":"Time of Day Effects on Peanut Herbicide Efficacy","authors":"O. W. Carter, E. Prostko","doi":"10.3146/ps18-18.1","DOIUrl":"https://doi.org/10.3146/ps18-18.1","url":null,"abstract":"\u0000 Recent research on the effects of time of d (TOD) when glufosinate is applied to cotton (Gossypium hirsutum L.) and several protoporphyrinogen-inhibiting herbicides in soybean (Glycine max L.) has growers concerned about potential TOD effects on peanut weed control. Consequently, research was conducted in 2015, 2016, and 2017 to determine if TOD influences the performance of peanut herbicides acifluorfen, bentazon, imazapic, lactofen, paraquat, and 2,4-DB. Both non- (bare-ground) and in-crop (peanut) studies were conducted. For non-crop, paraquat plus bentazon plus acifluorfen plus S-metolachlor, imazapic plus S-metolachlor plus 2,4-DB, and lactofen plus S-metolachlor plus 2,4-DB were applied to Palmer amaranth and a non-uniform mixture of annual grasses including Urochloa texana (Buckley), Dactyloctenium aegyptium (L.), Eleusine indica (L.), Digitaria spp. at 7:00, 12:00, 17:00, and 22:00 hr. For in-crop studies, two peanut weed control programs were used and herbicide programs were applied at the same TOD. Herbicides were paraquat plus acifluorfen plus bentazon plus S-metolachlor (EPOST) followed by imazapic plus S-metolachlor plus 2,4-DB, or lactofen plus S-metolachlor plus 2,4-DB (POST). For the non-crop studies, a significant interaction between TOD and herbicide program was observed for the 7 d after treatment (DAT) rating of Palmer amaranth control. Control was reduced with imazapic applied at 22:00 hr. At 14 DAT, there was no TOD effect and control was reduced with all imazapic treatments due to ALS resistance. There was no interaction between TOD and herbicide program for annual grass control. Annual grass control was unacceptable (<50%) with lactofen. For in-crop studies, there was no interaction between TOD or herbicide program. Peanut injury was lower at 7:00 hr and 22:00 hr when compared to other timings. Lactofen was more injurious to peanut than imazapic. Palmer amaranth control was not influenced by timing or herbicide program. A reduction in sicklepod control was observed at the 22:00 hr timing and with lactofen. While TOD influenced peanut injury and weed control, peanut yield was not affected.","PeriodicalId":19823,"journal":{"name":"Peanut Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91192611","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":"Remembering our Past and How it Affected Our Present and Future","authors":"H. Valentine","doi":"10.3146/0095-3679-46.1a.78","DOIUrl":"https://doi.org/10.3146/0095-3679-46.1a.78","url":null,"abstract":"\u0000 Howard Valentine worked for Texas Instruments, Columbian Peanut, ADM, Golden Peanut Company, and from 1997 to 2018 as Director of Science and Technology for the American Peanut Council. He was the Executive Director for the Peanut Foundation from 1997 to 2016 and held several other industry positions including chair of multiple committees: Research Committee for the Southeastern Peanut Shellers Association, the Multi-crop Aflatoxin Working Group, the Research Committee and Peanut Quality Improvement Committees for the National Peanut Council. Howard became an APRES fellow in 2013, received the Coyt T. Wilson and the American Peanut Council Lifetime Achievement award in 2015, and received the Peanut Foundation Peanut Research and Education Award in 2018. Howard is married to his wife, Debra, and has two children, William and Ann. This is his speech to commemorate the 50th anniversary of APRES.","PeriodicalId":19823,"journal":{"name":"Peanut Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74828025","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}