Diagnosis and management of halo blight in Australian mungbeans: a review

Mungbean (Vigna radiata L. Wilczek var. radiata) is an important food crop cultivated on over 6 Mha throughout the world. Its short duration of 55–70 days, capacity to fix atmospheric nitrogen, and exceptional grain nutritional profile makes the crop a staple for smallholder and subsistence farmers. In Australia, mungbean is grown as a high-value export crop and established as a main summer rotation for dryland farmers. A major threat to the integrity of the industry is halo blight, a bacterial disease leading to necrotic lesions surrounded by a chlorotic halo that stunts and ultimately kills the plant. Caused by Pseudomonas savastanoi pv. phaseolicola, this seed-borne disease is extremely difficult to control, resulting in significant yield loss and production volatility. The challenge of managing halo blight is exacerbated by a wide host range that includes many legume and weed species, and the presence of multiple epidemiologically significant strains. Molecular technologies could play a pivotal role in addressing these issues. This review synthesises current and emerging technologies to develop improved management strategies for the control of halo blight in mungbean.

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Soil Nitrogen Movement under Sustainable Vegetable Production Systems

HortScience ◽

10.21273/hortsci.33.3.494f ◽

1998 ◽

Vol 33 (3) ◽

pp. 494f-495 ◽

Cited By ~ 1

Author(s):

Amy M. Johnson ◽

Greg D. Hoyt

Keyword(s):

Pest Management ◽

Soil Nitrogen ◽

Conservation Tillage ◽

Management Strategies ◽

Conventional Tillage ◽

Plant Diseases ◽

Vegetable Production ◽

Beneficial Arthropods ◽

Weed Species ◽

Available Nitrogen

An experiment was established to determine the effect of different tillage practices, vegetable crop rotations, and pest management strategies on crop yield, plant diseases, pest and beneficial arthropods, weed species changes over time, and soil environmental consequences. This poster describes nitrogen movement from the various treatments over a 3-year rotation. The treatments are: 1) conventional tillage with chemically based IPM; 2) conventional tillage with biologically based IPM; 3) conservation tillage with chemically based IPM; 4) conservation tillage with biologically based IPM; and 5) conventional tillage with no fertilizer or pest management. Mid-season soil analyses with depth showed chemical-fertilized plowed and conservation-tilled treatments with more soil available nitrogen at most depths compared to the biological-based IPM systems (soybean meal was used as a nitrogen source). However, the biological-based systems did supply enough soil nitrogen to produce similar yield results as the chemical-based systems. Less soil nitrate was measured in the 30- to 90-cm depths at harvest from the biological-based systems than chemical-based systems. Conservation-tilled systems had greater nitrate with depth compared to conventional-tilled systems.

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Factors affecting Cyperus difformis seed germination and seedling emergence

Planta Daninha ◽

10.1590/s0100-83582013000400008 ◽

2013 ◽

Vol 31 (4) ◽

pp. 823-832 ◽

Cited By ~ 7

Author(s):

A. Derakhshan ◽

J. Gherekhloo

Keyword(s):

Seed Germination ◽

Integrated Management ◽

Germination Rate ◽

Seedling Emergence ◽

Management Strategies ◽

Soil Surface ◽

Weed Species ◽

Factors Affecting ◽

Cyperus Difformis ◽

Emergence Patterns

Specific knowledge about the dormancy, germination, and emergence patterns of weed species aids the development of integrated management strategies. Laboratory studies were conducted to determine the effect of several environmental factors on seed germination and seedling emergence of Cyperus difformis. Germination of freshly harvested seeds was inhibited by darkness; however, when seeds were subsequently transferred to complete light they germinated readily. Our results showed that 2 wk of cold stratification overcome the light requirement for germination. Seeds of C. difformis were able to germinate over a broad range of temperatures (25/15, 30/20, 35/25, and 40/30 ºC day/night). The response of germination rate to temperature was described as a non-linear function. Based on model outputs, the base, the optimum and the ceiling temperatures were estimated as 14.81, 37.72 and 45 ºC, respectively. A temperature of 120 ºC for a 5 min was required to inhibit 50% of maximum germination. The osmotic potential and salinity required for 50% inhibition of maximum germination were -0.47 MPa and 135.57 mM, respectively. High percentage of seed germination (89%) was observed at pH=6 and decreased to 12% at alkaline medium (pH 9) pH. Seeds sown on the soil surface gave the greatest percentage of seedling emergence, and no seedlings emerged from seeds buried in soil at depths of 1 cm.

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Germination Biology of Sesbania (Sesbania cannabina): An Emerging Weed in the Australian Cotton Agro-environment

Weed Science ◽

10.1017/wsc.2018.62 ◽

2018 ◽

Vol 67 (1) ◽

pp. 68-76 ◽

Cited By ~ 2

Author(s):

Nadeem Iqbal ◽

Sudheesh Manalil ◽

Bhagirath S. Chauhan ◽

Steve W. Adkins

Keyword(s):

Seed Germination ◽

Management Strategies ◽

Moisture Stress ◽

Integrated Weed Management ◽

Burial Depth ◽

Weed Species ◽

Physical Dormancy ◽

Sesbania Cannabina ◽

Wide Range ◽

The Impact

AbstractSesbania [Sesbania cannabina(Retz.) Pers.] is a problematic emerging weed species in Australian cotton-farming systems. However, globally, no information is available regarding its seed germination biology, and better understanding will help in devising superior management strategies to prevent further infestations. Laboratory and glasshouse studies were conducted to evaluate the impact of various environmental factors such as light, temperature, salt, osmotic and pH stress, and burial depth on germination and emergence of two Australian biotypes ofS. cannabina. Freshly harvested seeds of both biotypes possessed physical dormancy. A boiling-water scarification treatment (100±2 C) of 5-min duration was the optimum treatment to overcome this dormancy. Once dormancy was broken, the Dalby biotype exhibited a greater germination (93%) compared with the St George biotype (87%). The nondormant seeds of both biotypes showed a neutral photoblastic response to light and dark conditions, with germination marginally improved (6%) under illumination. Maximum germination of both biotypes occurred under an alternating temperature regime of 30/20 and 35/25 C and under constant temperatures of 32 or 35 C, with no germination at 8 or 11 C. Seed germination of both biotypes decreased linearly from 87% to 14% with an increase in moisture stress from 0.0 to −0.8 MPa, with no germination possible at −1.0 MPa. There was a gradual decline in germination for both biotypes when imbibed in a range of salt solutions of 25 to 250 mM, with a 50% reduction in germination occurring at 150 mM. Both biotypes germinated well under a wide range of pH values (4.0 to 10.0), with maximum germination (94%) at pH 9.0. The greatest emergence rate of the Dalby (87%) and St George (78%) biotypes was recorded at a burial depth of 1.0 cm, with no emergence at 16.0 cm. Deep tillage seems to be the best management strategy to stopS. cannabina’s emergence and further infestation of cotton (Gossypium hirsutumL.) fields. The findings of this study will be helpful to cotton agronomists in devising effective, sustainable, and efficient integrated weed management strategies for the control ofS. cannabinain cotton cropping lands.

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Analysis of Challenges Facing Rice Processing in Nigeria

Journal of Food Processing ◽

10.1155/2015/893673 ◽

2015 ◽

Vol 2015 ◽

pp. 1-6 ◽

Cited By ~ 9

Author(s):

A. S. Ajala ◽

A. Gana

Keyword(s):

Decision Making ◽

Growth Rate ◽

Developing Countries ◽

Population Growth Rate ◽

Developed Countries ◽

Small Scale ◽

Basic Information ◽

Food Crop ◽

Important Food ◽

Rice Processing

Rice is the most economically important food crop in many developing countries and has also become a major crop in many developed countries where its consumption has increased considerably. It has become necessary to meet the demand of the world’s current population growth rate, and the least costly means for achieving this aim is to increase rice productivity, wherever possible. The main challenges encountered by rice processors in Nigeria are to find appropriate solutions for quality rice processing. Therefore this work provides basic information about the challenges of rice processing and focuses on the challenges faced by the small scale rice processors and reasons for continuous rice importation with a view to guiding decision-making to be self-sufficient in rice production, thereby making some improvement in Nigerian economy.

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Interactions of Nitrogen Source and Rate and Weed Removal Timing Relative to Nitrogen Content in Corn and Weeds and Corn Grain Yield

International Scholarly Research Notices ◽

10.1155/2017/8961367 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Alexandra M. Knight ◽

Wesley J. Everman ◽

David L. Jordan ◽

Ronnie W. Heiniger ◽

T. Jot Smyth

Keyword(s):

Grain Yield ◽

Weed Management ◽

Management Strategies ◽

Field Studies ◽

Weed Species ◽

Weed Interference ◽

Coated Urea ◽

N Fertility ◽

Corn Grain ◽

Corn Grain Yield

Adequate fertility combined with effective weed management is important in maximizing corn (Zea mays L.) grain yield. Corn uptake of nitrogen (N) is dependent upon many factors including weed species and density and the rate and formulation of applied N fertilizer. Understanding interactions among corn, applied N, and weeds is important in developing management strategies. Field studies were conducted in North Carolina to compare corn and weed responses to urea ammonium nitrate (UAN), sulfur-coated urea (SCU), and composted poultry litter (CPL) when a mixture of Palmer amaranth (Amaranthus palmeri S. Wats.) and large crabgrass (Digitaria sanguinalis L.) was removed with herbicides at heights of 8 or 16 cm. These respective removal timings corresponded with 22 and 28 days after corn planting or V2 and V3 stages of growth, respectively. Differences in N content in above-ground biomass of corn were noted early in the season due to weed interference but did not translate into differences in corn grain yield. Interactions of N source and N rate were noted for corn grain yield but these factors did not interact with timing of weed control. These results underscore that timely implementation of control tactics regardless of N fertility management is important to protect corn grain yield.

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Seed germination ecology of Conyza stricta Willd. and implications for management

PLoS ONE ◽

10.1371/journal.pone.0244059 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0244059

Author(s):

Safdar Ali ◽

Fakhar Din Khan ◽

Rehmat Ullah ◽

Rahmat Ullah Shah ◽

Saud Alamri ◽

...

Keyword(s):

Seed Germination ◽

Osmotic Potential ◽

Cropping Systems ◽

Seedling Emergence ◽

Management Strategies ◽

Conservation Agriculture ◽

Weed Species ◽

Seed Burial ◽

Germination Ecology ◽

Tillage Practices

Numerous cropping systems of the world are experiencing the emergence of new weed species in response to conservation agriculture. Conyza stricta Willd. is being a newly emerging weed of barley-based cropping systems in response to conservational tillage practices. Seed germination ecology of four populations (irrigated, rainfed, abandoned and ruderal habitats) was studied in laboratory and greenhouse experiments. The presence/absence of seed dormancy was inferred first, which indicated seeds were non-dormant. Seed germination was then recorded under various photoperiods, constant and alternating day/night temperatures, and pH, salinity and osmotic potential levels. Seedling emergence was observed from various seed burial depths. Seeds of all populations proved photoblastic and required 12-hour light/dark period for germination. Seeds of all populations germinated under 5–30°C constant temperature; however, peak germination was recorded under 17.22–18.11°C. Nonetheless, the highest germination was noted under 20/15°C alternating day/night temperature. Ruderal and irrigated populations better tolerated salinity and germinated under 0–500 mM salinity. Similarly, rainfed population proved more tolerant to osmotic potential than other populations. Seeds of all populations required neutral pH for the highest germination, whereas decline was noted in germination under basic and alkaline pH. Seedling emergence was retarded for seeds buried >2 cm depth and no emergence was recorded from >4 cm depth. These results add valuable information towards our understanding of seed germination ecology of C. stricta. Seed germination ability of different populations under diverse environmental conditions suspects that the species can present severe challenges in future if not managed. Deep seed burial along with effective management of the emerging seedlings seems a pragmatic option to manage the species in cultivated fields. However, immediate management strategies are needed for rest of the habitats.

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Seleksi Berbasis Marka Molekuler pada Padi Generasi F2 Guna Merakit Galur Padi Harapan Tahan Wereng Coklat

Agrikultura ◽

10.24198/agrikultura.v27i1.8471 ◽

2016 ◽

Vol 27 (1) ◽

Author(s):

Nono Carsono ◽

Gigih Ibnu Prayoga ◽

Neni Rostini ◽

Danar Dono

Keyword(s):

Ssr Markers ◽

Simple Sequence Repeat ◽

Yield Loss ◽

Insect Pest ◽

Brown Planthopper ◽

F2 Population ◽

Significant Yield ◽

F2 Generation ◽

F2 Progeny ◽

Simple Sequence

ABSTRACTMolecular Marker-based Selection on F2 Progeny for Development of Promising Rice Lines Resistant to Brown PlanthopperBrown planthopper (BPH) is the major insect pest of rice and accounts for significant yield loss. This experiment was aimed to develop BC1F1 and F3 brown planthopper resistant rice lines. Selection on the basis of SSR markers can be done by using two polymorphic SSR markers, i.e., RM586 dan RM8213, which screened from eight SSR markers for BPH resistant. Sixty-three F2 genotypes from IP-1 (derived from IR-64 x PTB-33) population and twenty F2 genotypes from PP-11 (derived from Pandan Wangi x PTB-33) population were selected and will be used for further research by selfed and backcrossed to recipient parents. Chi-squares test for segregation of DNA bands in F2 generation showed that RM8213 fitted with 1:2:1 Mendelian ratio for controlling photosynthetic rates and trichomes length in IP-1 population. This information could be used in programs to develop a durable brown planthopper resistant rice cultivar.Keywords: BPH, F2 population, Moleculer marker, SSRABSTRAKWereng coklat merupakan salah satu hama utama pada tanaman padi yang mampu menurunkan produksi padi secara nyata. Penelitian ini bertujuan untuk memperoleh galur-galur padi F2 yang memiliki marka-marka yang berasosisasi dengan ketahanannya terhadap wereng coklat. Seleksi pada galur padi F2 hasil persilangan telah dilakukan melalui teknik marka molekuler Simple Sequence Repeat (SSR) menggunakan dua marka SSR yang menunjukkan polimorphisme yaitu RM586 dan RM8213 dari delapan marka yang diskrining. Sebanyak 63 genotip dari populasi IP-1 (hasil persilangan IR-64 x PTB-33) dan 20 genotip dari populasi PP-11 (hasil persilangan Pandan Wangi x PTB-33) untuk disilangkan sendiri maupun disilang balik dengan tetua recipient. Selain itu, hasil analisis Chi-Kuadrat untuk segregasi pita DNA menunjukkan bahwa primer RM8213 memiliki rasio 1:2:1 (dominasi tidak sempurna) dalam mengontrol karakter laju fotosintesis dan panjang trikoma terhadap wereng coklat pada populasi IP-1. Informasi yang diperoleh dari penelitian ini nantinya dapat digunakan untuk program perakitan kultivar padi tahan wereng coklat yang durable.Kata Kunci: Marka molekuler, Populasi F2, SSR, Wereng coklat

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A BRIEF REVIEW FOR IDENTIFICATION AND DETECTION OF POTATO VIRUSES

World Journal of Biology and Biotechnology ◽

10.33865/wjb.001.01.0003 ◽

2016 ◽

Vol 1 (1) ◽

pp. 33 ◽

Cited By ~ 1

Author(s):

Madiha Urooj ◽

Uzma Arif ◽

Anisa Intikhab

Keyword(s):

Potato Crop ◽

Abiotic Factors ◽

Review Article ◽

Pivotal Role ◽

Yield Reduction ◽

Human Consumption ◽

Yield Losses ◽

Food Crop ◽

Potato Viruses ◽

Significant Yield

Potato is ranked fourth among the food crop and fifth for human consumption. It provides more yield and calories production as compare to cereals. Fungal, viral, viroid, bacteria, nematode, phytoplasmas and abiotic factors play a pivotal role for yield reduction of potato crop. Viruses known to infect potato in Pakistan include PVA, PVM, PVS, PVX, PVY, PLRV and PMTV. Increasing incidence of PVX and PVY in main potato growing areas of Pakistan is getting an alarming position and PLRV has caused significant yield losses. Present review article demonstrate different techniques for diagnostics of major potato viruses.

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The Improvement of Mini Tuber Production of Granola Potato Cultivar in Aeroponics System

Biosaintifika Journal of Biology & Biology Education ◽

10.15294/biosaintifika.v13i1.27714 ◽

2021 ◽

Vol 13 (1) ◽

pp. 77-83

Author(s):

Sugiyono Sugiyono ◽

Lucky Prayoga ◽

Elly Proklamasiningsih ◽

Khavid Faozi ◽

Rendie Prasetyo

Keyword(s):

Potato Cultivar ◽

Potato Production ◽

Tuber Formation ◽

Planting Density ◽

Food Crop ◽

Important Food ◽

High Quality ◽

Plant Materials ◽

Tuber Production ◽

Surrounding Areas

Potato is an important food crop in both developed and developing countries and it is the fourth most important food crop after wheat, maize, and rice. Potato production in Indonesia has decreased in recent years, mainly due to the use of low quality tuber seed. The objective of this research was to determine the effect of plant materials, types of nutrients, and planting density on mini tuber formation, as well as to determine the best aeroponics conditions for mini tuber formation of Granola cultivar of potato. This research has been carried out experimentally using a Split-split Plot Design. The main plot was planting materials which consisted of plantlet and knol. The subplot was the type of nutrition media which consisted of Farran nutrition, Otazu nutrition, and AB-commercial mix. The sub-sub-plot was planting density which consisted of 50, 75, and 100 plants/m2. The research results showed that knol planted in aeroponics system on AB-commercial mix at a planting density of 75 plants/m2 resulted in the best mini-tuber production. In this study, for the first time three important factors for potato mini-tuber production have thoroughly been investigated in Indonesia. This finding will be used by Kledung Horticultural Seed Garden, Temanggung, for mass production of high-quality mini-tuber seed, which in turn will provide sufficient tuber seed for the farmer in its surrounding areas. By increasing the production of high-quality tuber seed, it is expected that it will contribute to the improvement of potato productivity and increase Indonesian potato production.

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Predicting Yield Losses in Rice Mixed-Weed Species Infestations in California

Weed Science ◽

10.1614/ws-d-16-00079.1 ◽

2016 ◽

Vol 65 (1) ◽

pp. 61-72 ◽

Cited By ~ 6

Author(s):

Whitney B. Brim-DeForest ◽

Kassim Al-Khatib ◽

Albert J Fischer

Keyword(s):

Yield Loss ◽

Information Criterion ◽

Average Error ◽

Canopy Closure ◽

Weed Species ◽

Major Barrier ◽

Combined Models ◽

Relative Cover ◽

Predicted Values ◽

Using Data

Although many pests constrain rice production, weeds are considered to be the major barrier to achieving optimal yields. A predictive model based on naturally occurring mixed-species infestations in the field would enable growers to target the specific weed group that is the greatest contributor to yield loss, but as of now no such models are available. In 2013 and 2014, two empirical hyperbolic models were tested using the relative cover at canopy closure of groups of weed species as independent variables: grasses, sedges, broadleaves, grasses and sedges combined, grasses and broadleaves combined, and all weed species combined. Models were calibrated using data from experiments conducted at the California Rice Experiment Station, in Biggs, CA, and validated across four sites over 2 years, for a total of 7 site-year combinations. Of the three major weed groups, grasses, sedges, and broadleaves, the only groups positively related to yield loss in the multispecies infestation were grasses. At the model calibration site, grasses and sedges combined best predicted yield loss (corrected Akaike information criterion [AICc]=−21.5) in 2013, and grasses alone best predicted yield loss (AICc=−19.0) in 2014. Across the validation sites, the model using grasses and sedges combined was the best predictor in 5 out of 7 site-years. Accuracy of the predicted values at the model validation sites ranged from 6% mean average error to 17% mean average error. No single model and set of parameters accurately predicted losses across all years and locations, but relative cover of grasses and sedges combined at canopy closure was the best estimate over the most sites and years.

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