Plant Pathology Commons^™

Application Of Molecular Markers In Genetic Resources Management Of Perennial Ryegrass, R. Van Treuren

IGC Proceedings (1977-2023)

Key points

1. Molecular markers are effective tools to support traditional approaches in plant genetic resources management.
2. Genetic diversity assessed for perennial ryegrass by AFLP analysis revealed differentiation of populations occurring in traditional Dutch grasslands from commercial varieties, but not from populations occurring in Dutch nature reserves.
3. No specific conservation measures were recommended to maintain the genetic diversity of perennial ryegrass occurring in traditional Dutch grasslands.
4. Pollination rates estimated by microsatellite analysis for a rejuvenated population of a perennial ryegrass genebank accession were very well described by an inverse quadratic function of inter-plant distance between potential mating pairs, while recorded flowering …

Leaves Of High Yielding Perennial Ryegrass Contain Less Aggregated Rubisco Than S23, A. Kingston-Smith, P. W. Wilkins

IGC Proceedings (1977-2023)

Breeding diploid perennial ryegrass for improved dry matter yield under nitrogen-limiting conditions has reduced the nitrogen (N) concentration of the herbage (Wilkins et al., 2003). Reduced N concentration in the ruminant diet is one potential way to reduce losses of N to the environment by reducing the amount of N that animals excrete. The underlying physiological basis of this increased N-use efficiency in ryegrass was investigated.

Variability In Quantity And Composition Of Water Soluble Carbohydrates Among Irish Accessions And European Varieties Of Perennial Ryegrass, S. Mcgrath, S. Barth, A. Frohlich, M. Francioso, S. A. Lamorte, T. R. Hodkinson

IGC Proceedings (1977-2023)

The objective of this study was to identify perennial ryegrass accessions displaying high fructose and glucose contents and an improved ratio between fructose and glucose fractions across different time points throughout the year. Fructose and glucose are the main constituents of the water soluble carbohydrate (WSC) fraction in perennial ryegrass. For animal nutrition the amount of WSC is crucial as it is the primary energy source available to metabolise the intake of plant protein. The ratio between fructose and glucose fractions is important since fructosan chains, which are an excellent energy source for ruminants, are built from fructose. Furthermore the …

Introgression Breeding For Improvement Of Winter Hardiness In Lolium /Festuca Complex Using Androgenenesis, T. Yamada, Y. D. Guo, Y. Mizukami

IGC Proceedings (1977-2023)

Intergeneric hybrids between closely related Lolium and Festuca species are used to broaden the gene pool and provide plant breeders with options to combine complementary traits to develop robust but high quality grass varieties. Androgenesis was found to be an effective procedure for selecting Lolium-Festuca genotypes comprising gene combinations rarely or never recovered by conventional backcross breeding programs. Here we describe the optimisation of androgenesis in Lolium perenne x Festuca pratensis. The male fertility and freezing tolerance of the Festulolium microspore-derived progenies were analysed and these progenies were also analysed by using genomic in situ hybridisation (GISH). The object …

A New Napier Grass Stunting Disease In Kenya Associated With Phytoplasma, A. B. Orodho, S. I. Ajanga, P. Jones, P. O. Mudavadi

IGC Proceedings (1977-2023)

Napier grass (Pennisetum purpureum Schum) is a cultivated elephant grass native to Eastern and Central Africa forming the major livestock feed on East African smallholder dairy farms (Valk, 1990) as it is suitable for cut and carry zero-grazing management systems. Although several plant pathogens have been described historically they were seldom severe. However, in the 1970s there was an outbreak of snow mould fungal disease caused by Beniowskia spheroidea that attacked most varieties of napier grass. A napier grass variety (clone 13) was bred which is resistant to the disease. In the 1990s two major outbreaks of napier grass …

Studies Of Seed Characteristics Of Ecotypes Of Lucerne, Bromus And Agropyron In Response To Fusarium Oxysporum And F. Solani, M. A. Alizadeh

IGC Proceedings (1977-2023)

Vigorous seeds and seedlings are more resistant to pathogens than non-vigorous seeds and seedlings (Kim, 1994). Therefore, it is necessary to assess seed and seedling performance in response to seed borne fungi.

Genetic Analysis Of The Interaction Between The Host Perennial Ryegrass And The Crown Rust Pathogen (Puccinia Coronata F.Sp. Lolii), P. M. Dracatos, J. L. Dumsday, R. S. Olle, N. O. I. Cogan, M. P. Dobrowolski, K. F. Smith, J. W. Forster

IGC Proceedings (1977-2023)

Crown rust (Puccinia coronata f.sp lolii) is the most important fungal pathogen of perennial ryegrass (L.perenne L.). The physiological effects associated with infection include reduction of water soluble carbohydrate (WSC) reserves, causing decreased dry matter yield, digestibility and palatability for herbivores reared for meat, milk and wool production. Phenotypic variability of rust-infection in perennial ryegrass is likely to be due to environmental effects, as well as the interaction of defence and resistance genes in the grass and virulence genes in the pathogen. Classical and molecular genetic marker-based studies have previously detected both qualitative and quantitative resistance, due respectively …

Molecular Characterisation Of Bacterial Wilt Resistance In Lolium Multiflorum Lam., B. Studer, B. Boller, F. Windmer, U. K. Posselt, E. Bauer, R. Kölliker

IGC Proceedings (1977-2023)

Italian ryegrass (Lolium multiflorum Lam.), a forage grass of prime importance throughout the world, is adversely affected by the pathogen Xanthomonas translucens pv graminis. Breeding for resistant cultivars is the only practicable means of disease control. However, the inheritance of bacterial wilt resistance is largely unknown. The aim of our research is to elucidate genetic control of bacterial wilt resistance using molecular technologies such as genetic linkage mapping and the analysis of quantitative trait loci (QTL).

Ear Emergence Of Different Grass Species Under Finnish Growing Conditions, M. Niskanen, O. Niemeläinen, L. Jauhiainen

IGC Proceedings (1977-2023)

Timothy is the most commonly cultivated grass species in Finland. Swards cultivated for silage of hay are of pure timothy or timothy is the dominant species of the mixture. Successful timing of harvesting of the primary growth is very critical in Northern latitudes where the stand develops very rapidly at daylengths of above 18 hours with a daily mean temperature close to 20 °C. The primary growth has to be harvested within a very short period to obtain a yield of high and uniform quality. Short harvesting periods require high capacity harvest machinery which lead to high costs. If it …

The Effect Of Harvest Management On Forage Production And Self-Reseeding Potential Of Italian Ryegrass (Lolium Multiflorum L.), P. W. Bartholomew, R. D. Williams

IGC Proceedings (1977-2023)

Italian ryegrass (Lolium multiflorum L.) (IRG) can be managed to produce a seed output sufficient for effective re-establishment, without compromising forage yield, it may provide an alternative to perennial cool-season grasses in the Southern Great Plains of the U.S.A. The reduction in cost of replanting and avoidance of cultivation offered by a self-seeding crop may be particularly useful in low-input production systems. We examined the effect of dates of initial harvest in spring and of partial harvests on forage yield, seed output and re-establishment of Italian ryegrass.

The Influence Of Fertiliser Application To Strip-Sown Grasslands On Herbage Production And Quality, A. Kohoutek, P. Komárek, V. Odstrčilová, P. Nerušil

IGC Proceedings (1977-2023)

To increase the productivity of dairy cattle in the Czech Republic requires an improvement in herbage quality and an increase in the net energy of herbage. The decrease in cattle numbers by 50 % and the expansion of the grassland area both result in a surplus of feedstuffs of low quality. Introduction of strip-seeding of legumes and grasses into grasslands in interaction with fertilisation provides a possible solution to this problem.

Constraints On Dairy Cattle Production From Locally Available Forages In Bangladesh, M. A. S. Khan

IGC Proceedings (1977-2023)

The productivity of milk producing animals in Bangladesh is low because of low individual yield and poor fertility. The reasons for the low productivity are complex but, in order of priority, appear to be (a) the imbalanced nature of the nutrients that arise from the digestion of the forage resources, (b) the incidence of disease/parasitism, and (c) the often harsh climatic circumstances. Thus, the purpose of this study was to find out the practical constraints on dairy cattle production from locally available forages under small holding village conditions of Bangladesh.

Pasture Management In Deer Farms In Mauritius, P. Grimaud, P. Thomas, J. Sauzier

IGC Proceedings (1977-2023)

Rusa deer (Cervus timorensis russa) were introduced into Mauritius in 1639, and with a population of 65,000 deer now provide the first source of red meat in the island. From June to September, the hunting period, extensive ranches ensure the venison market, while intensive farms provide it for the rest of the year. A pasture survey was carried out over 3 years to advise deer farmers on their sward management.

Soybean GmSaul1, A Bona Fide U-Box E3 Ligase, Negatively Regulates Immunity Likely Through Repressing The Activation Of GmMpk3, Jun-Mei Li, Mei-Yan Ye, Chaofeng Wang, Xiao-Han Ma, Ni-Ni Wu, Chen-Li Zhong, Yanjun Zhang, Ninghui Cheng, Paul A. Nakata, Lirong Zeng, Jian-Zhong Liu

Center for Plant Science Innovation: Faculty Publications

E3 ubiquitin ligases play important roles in plant immunity, but their role in soybean has not been investigated previously. Here, we used Bean pod mottle virus (BPMV)-mediated virusinduced gene silencing (VIGS) to investigate the function of GmSAUL1 (Senescence-Associated E3 Ubiquitin Ligase 1) homologs in soybean. When two closely related SAUL1 homologs were silenced simultaneously, the soybean plants displayed autoimmune phenotypes, which were significantly alleviated by high temperature, suggesting that GmSAUL1a/1b might be guarded by an R protein. Interestingly, silencing GmSAUL1a/1b resulted in the decreased activation of GmMPK6, but increased activation of GmMPK3 in response to flg22, …

Genome Assembly Of The Brassicaceae Diploid Orychophragmus Violaceus Reveals Complex Whole-Genome Duplication And Evolution Of Dihydroxy Fatty Acid Metabolism, Fan Huang, Peng Chen, Xinyu Tang, Ting Zhong, Taihua Yang, Chinedu Charles Nwafor, Chao Yang, Xianhong Ge, Hong An, Zaiyun Li, Edgar B. Cahoon, Chunyu Zhang

Center for Plant Science Innovation: Faculty Publications

Orychophragmus violaceus is a Brassicaceae species widely cultivated in China, particularly as a winter cover crop in northern China because of its low-temperature tolerance and low water demand. Recently, O. violaceus has also been cultivated as a potential industrial oilseed crop because of its abundant 24- carbon dihydroxy fatty acids (diOH-FAs), which contribute to superior high-temperature lubricant properties. In this study, we performed de novo assembly of the O. violaceus genome. Whole-genome synteny analysis of the genomes of its relatives demonstrated that O. violaceus is a diploid that has undergone an extra whole-genome duplication (WGD) after the Brassicaceae-specific α-WGD event, …

Plant Breeding Advancements With “Crispr-Cas” Genome Editing Technologies Will Assist Future Food Security, M. Ahmad

Center for Plant Science Innovation: Faculty Publications

Genome editing techniques are being used to modify plant breeding, which might increase food production sustainably by 2050. A product made feasible by genome editing is becoming better known, because of looser regulation and widespread acceptance. The world’s population and food supply would never have increased proportionally under current farming practices. The development of plants and food production has been greatly impacted by global warming and climate change. Therefore, minimizing these effects is crucial for agricultural production that is sustainable. Crops are becoming more resilient to abiotic stress because of sophisticated agricultural practices and a better understanding of the abiotic …

Discriminating Stay-Green Grasses Using Hyperspectral Imaging And Chemometrics, J. Taylor, B. Moore, J. J. Rowland, H. Thomas, H. J. Ougham

IGC Proceedings (1977-2023)

Screening of plant collections for traits can be expensive, in terms of the number of plants to be screened, the duration of the plant lifecycle and the required observations. This study describes the application of a non-invasive method, hyperspectral imaging, combined with multivariate analysis, to distinguish between homozygous wild-type (YY) Lolium multiflorum and Lolium multiflorum F2 back cross plants heterozygous for y, a recessive Festuca pratensis stay-green gene (Thomas et al., 1997).

Non-Destructive Assessment Of Quality And Yield For Grass-Breeding, A. G. T. Schut, M. J. J. Pustjens, P. W. Wilkins, J. Meuleman, P. Reyns, A. Lovatt, G. W. A. M. Van Der Heijden

IGC Proceedings (1977-2023)

Selection of cultivars has, until now, been based mainly on dry matter (DM) yields because of the high costs of sampling and chemical analysis. Imaging spectroscopy could reduce costs by limiting sampling and harvesting of individual plots to reference samples (Schut et al., accepted). In this study, the prediction accuracy of DM yields and chemical composition with imaging spectroscopy is evaluated for cultivar selection purposes.

Root Senescence In Red Clover (Trifolium Pratense L.), K. J. Webb, E. Tuck, S. Heywood

IGC Proceedings (1977-2023)

Legume root systems form a mosaic of living, ageing and dead roots and nodules. The balance between these stages alters during plant development. Stressful events (drought, temperature change, reduced carbon supply, etc.) disturb the balance (Butler et al., 1959). Effects of root and nodule death on soil structure, composition and leaching and on plant persistency are understood poorly. Plants with differing senescence patterns are useful tools to study these effects. Molecular studies of root senescence need detailed knowledge of the process and timing of root senescence and death. Biochemical and histochemical markers of senescence were used to generate preliminary …

Development Of Simple Sequence Repeat (Ssr) Markers And Their Use To Assess Genetic Diversity In Apomictic Guineagrass (Panicum Maximum Jacq.), M. Ebina, Kaori Kouki, S. Tsuruta, M. Takahara, M. Kobayashi, T. Yamamoto, K. Nakajima, H. Nakagawa

IGC Proceedings (1977-2023)

Guineagrass is an important and widely grown tropical forage grass. Despite its importance and increasing popularity, only little is known about its genetic diversity (Ebina et al., 2001). Such information is useful for the selection of diverse parents in breeding programmes. Moreover, no simple sequence repeat (SSR) markers have been reported in any apomixis species. In this study SSR markers were developed and used to investigate genetic diversity in germplasm of apomictic guineagrass.