twenty-two bread wheat cultivars along with susceptible (sholeh) and resistant (azadi) control cultivars were evaluated for resistance to russian wheat aphid of two growth stages including seedling and stem elongation in greenhouse. five adult aphids per plant were used for infestation. leaf chlorosis at seedling and stem elongation stages and leaf rolling at seedling stage were measured. other...

ABSTRACT Partial resistance to Septoria tritici blotch (STB) and its inheritance were investigated in a doubled-haploid population of a cross between cvs. Arina and Riband. The former has good partial resistance whereas the latter is susceptible. In adult plant trials in polytunnels, STB disease scores were negatively correlated with heading date. Resistance was not specific to any of the three...

To determine the relationship between changes in soil physical properties due to tillage and growth of loblolly pine (Pinus taeda L.) seedlings, we measured soil moisture and penetration resistance for a range of tillage treatments on two Upper Coastal Plain sites in Georgia and correlated these measurements to the growth of individual seedlings. The five tillage treatments were: no-till (NT), ...

the use of heavy machinery in forestry operations such as logging has increased worldwide during the last decades. however, these machines may seriously influence the soil ecosystem as they induce rutting, disturbing the upper soil layers, and soil compaction. severe compaction of soil adversely affects the growth of plants.this study was done by using a penetration resistance experiment in a g...

Stagonospora nodorum blotch (SNB) caused by Stagonospora nodorum is a severe disease of wheat (Triticum aestivum) in many areas of the world. S. nodorum affects both seedling and adult plants causing necrosis of leaf and glume tissue, inhibiting photosynthetic capabilities, and reducing grain yield. The aims of this study were to evaluate disease response of 280 doubled haploid (DH) individuals...

Stem rust of wheat caused by the fungal pathogen Puccinia graminis f. sp. tritici historically caused major yield losses of wheat worldwide. To understand the genetic basis of stem rust resistance in contemporary North American spring wheat, genome-wide association analysis (GWAS) was conducted on an association mapping panel comprised of 250 elite lines. The lines were evaluated in separate nu...

Sclerotinia stem rot is one of the most devastating diseases of rapeseed in China, which causes yield loss ranging from 10 to 80%. The objective of this study was to detect the QTLs associated with this disease. A partial sclerotinia resistance rapeseed line M083 was crossed with a sensitive one APL01, and the BC1F1 derived from this cross was used as a mapping population. The 182 lines of BC1F...

The effects of Meloidogyne incognita or M. javanica at five initial inoculum levels of 20, 100, 200, 1,000, and 2,000 eggs and infective juveniles per seedling on 'Floradade,' 'Nemarex,' 'Patriot,' and 'PI 129149-2(sib)-5' tomatoes maintained at 25 or 32.5 C were studied. The number of egg masses on roots of the susceptible cultivar Floradade was similar for both species of root-knot nematodes ...

Stem rust, caused by Puccinia graminis (Pgt), is a damaging disease of wheat that can be controlled by utilizing effective stem rust resistance genes. 'Thatcher' wheat carries complex resistance to stem rust that is enhanced in the presence of the resistance gene Lr34. The purpose of this study was to examine APR in 'Thatcher' and look for genetic interactions with Lr34. A RIL population was te...