Wheat biomass and yield increased when populations of the root-lesion nematode (Pratylenchus thornei) were reduced through sequential rotation of partially resistant winter and summer crops

2014 ◽  
Vol 65 (3) ◽  
pp. 227 ◽  
Author(s):  
K. J. Owen ◽  
T. G. Clewett ◽  
K. L. Bell ◽  
J. P. Thompson
Keyword(s):  
Grain Yield ◽  
Crop Rotation ◽  
Yield Loss ◽  
Soil Depth ◽  
Wheat Yield ◽  
Broad Host Range ◽  
Root Lesion Nematode ◽  
Pratylenchus Thornei ◽  
Host Status ◽  
Lesion Nematode

The root-lesion nematode, Pratylenchus thornei, can reduce wheat yields by >50%. Although this nematode has a broad host range, crop rotation can be an effective tool for its management if the host status of crops and cultivars is known. The summer crops grown in the northern grain region of Australia are poorly characterised for their resistance to P. thornei and their role in crop sequencing to improve wheat yields. In a 4-year field experiment, we prepared plots with high or low populations of P. thornei by growing susceptible wheat or partially resistant canaryseed (Phalaris canariensis); after an 11-month, weed-free fallow, several cultivars of eight summer crops were grown. Following another 15-month, weed-free fallow, P. thornei-intolerant wheat cv. Strzelecki was grown. Populations of P. thornei were determined to 150 cm soil depth throughout the experiment. When two partially resistant crops were grown in succession, e.g. canaryseed followed by panicum (Setaria italica), P. thornei populations were <739/kg soil and subsequent wheat yields were 3245 kg/ha. In contrast, after two susceptible crops, e.g. wheat followed by soybean, P. thornei populations were 10 850/kg soil and subsequent wheat yields were just 1383 kg/ha. Regression analysis showed a linear, negative response of wheat biomass and grain yield with increasing P. thornei populations and a predicted loss of 77% for biomass and 62% for grain yield. The best predictor of wheat yield loss was P. thornei populations at 0–90 cm soil depth. Crop rotation can be used to reduce P. thornei populations and increase wheat yield, with greatest gains being made following two partially resistant crops grown sequentially.

Yield response in chickpea cultivars and wheat following crop rotations affecting population densities of Pratylenchus thornei and arbuscular mycorrhizal fungi

2014 ◽  
Vol 65 (5) ◽  
pp. 428 ◽  
Author(s):  
R. A. Reen ◽  
J. P. Thompson ◽  
T. G. Clewett ◽  
J. G. Sheedy ◽  
K. L. Bell
Keyword(s):  
Grain Yield ◽  
Crop Rotation ◽  
Mycorrhizal Fungi ◽  
Soil Depth ◽  
Arbuscular Mycorrhizal ◽  
Yield Response ◽  
First Year ◽  
Pratylenchus Thornei ◽  
Tolerance Indices ◽  
Chickpea Cultivars

In Australia, root-lesion nematode (RLN; Pratylenchus thornei) significantly reduces chickpea and wheat yields. Yield losses from RLN have been determined through use of nematicide; however, nematicide does not control nematodes in Vertosol subsoils in Australia’s northern grains region. The alternative strategy of assessing yield response, by using crop rotation with resistant and susceptible crops to manipulate nematode populations, is poorly documented for chickpea. Our research tested the effectiveness of crop rotation and nematicide against P. thornei populations for assessing yield loss in chickpea. First-year field plots included canola, linseed, canaryseed, wheat and a fallow treatment, all with and without the nematicide aldicarb. The following year, aldicarb was reapplied and plots were re-cropped with four chickpea cultivars and one intolerant wheat cultivar. Highest P. thornei populations were after wheat, at 0.45–0.6 m soil depth. Aldicarb was effective to just 0.3 m for wheat and 0.45 m for other crops, and increased subsequent crop grain yield by only 6%. Canola, linseed and fallow treatments reduced P. thornei populations, but low mycorrhizal spore levels in the soil after canola and fallow treatments were associated with low chickpea yield. Canaryseed kept P. thornei populations low throughout the soil profile and maintained mycorrhizal spore densities, resulting in grain yield increases of up to 25% for chickpea cultivars and 55% for wheat when pre-cropped with canaryseed compared with wheat. Tolerance indices for chickpeas based on yield differences after paired wheat and canaryseed plots ranged from 80% for cv. Tyson to 95% for cv. Lasseter and this strategy is recommended for future use in assessing tolerance.

scholarly journals Resistance of Wheat Genotypes to Root-Lesion Nematode (Pratylenchus thornei) Can be Used to Predict Final Nematode Population Densities, Crop Greenness, and Grain Yield in the Field

2020 ◽  
Vol 110 (2) ◽  
pp. 505-516 ◽  
Author(s):  
J. P. Thompson ◽  
J. G. Sheedy ◽  
N. A. Robinson
Keyword(s):  
Grain Yield ◽  
Nematode Population ◽  
Root Lesion Nematode ◽  
Population Densities ◽  
Wheat Genotypes ◽  
Final Population ◽  
Pratylenchus Thornei ◽  
Principal Axes ◽  
Australian Wheat ◽  
Lesion Nematode

The root-lesion nematode Pratylenchus thornei is a major pathogen of wheat (Triticum aestivum) in many regions globally. Resistance of wheat genotypes to P. thornei can be determined from final nematode population densities in glasshouse experiments but combining results across multiple experiments presents challenges. Here, we use a factor analytic method for multiexperiment analysis of final population densities of P. thornei for 1,096 unique wheat genotypes in 22 glasshouse experiments. The resistance to P. thornei of the genotypes was effectively represented by a two-factor model with rotation of the axes to a principal components solution. Principal axes 1 and 2 (PA1 and PA2) accounted for 79 and 11% of the genetic variance, respectively, over all experiments. Final population densities of P. thornei as empirical best linear unbiased predictors (PA[1+2]-eBLUPs) from the combined glasshouse experiments were highly predictive (P < 0.001) of final nematode population densities in the soil profile, crop canopy greenness (normalized difference vegetation index), and grain yield of wheat genotypes in P. thornei-infested fields in the Australian subtropical grain region. Nine categories of resistance ratings for wheat genotypes from resistant to very susceptible were based on subdivision of the range of PA(1+2)-eBLUPs for use in growers’ sowing guides. Nine genotypes were nominated as references for future resistance experiments. Most (62%) Australian wheat genotypes were in the most susceptible three categories (susceptible, susceptible to very susceptible, and very susceptible). However, resistant germplasm characterized in this study could be used in plant breeding to considerably improve the overall resistance of Australian wheat crops.

scholarly journals Impacts of Root-Lesion Nematode (Pratylenchus thornei) on Plant Nutrition, Biomass, Grain Yield and Yield Components of Susceptible/Intolerant Wheat Cultivars Determined by Nematicide Applications

Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 296
Author(s):  
John P. Thompson ◽  
Timothy G. Clewett
Keyword(s):  
Grain Yield ◽  
Yield Components ◽  
Root Zone ◽  
Wheat Cultivars ◽  
Root Lesion Nematode ◽  
Population Densities ◽  
Poor Growth ◽  
Pratylenchus Thornei ◽  
Lesion Nematode ◽  
The Impact

Field experiments testing rates of various nematicides, with and without NPZn fertiliser, were analysed to investigate how root-lesion nematode (Pratylenchus thornei) affects growth and yield components of susceptible/intolerant wheat cultivars in a subtropical environment. Plant response to nematode attack was assessed by regression and principal components analyses of various plant parameters at different crop development stages, in relation to different nematode population densities in the roots and root-zone soil. Reduction in P. thornei population densities by nematicides resulted in increased numbers of tillers, plant biomass, N and P concentrations and uptakes, numbers of spikes and kernels, and grain yield. Grain yield was strongly correlated with number of kernels, biomass and number of spikes, and negatively correlated with number of P. thornei in the root-zone soil at stem elongation. This study showed that P. thornei damage to roots decreased wheat yield through limiting N and P concentrations and uptakes in plant tops causing poor growth that commenced early and continued through the life of the crop. Genetic, environmental and management factors that reduce population densities of P. thornei, and decrease the impact of the nematodes starting in early crop growth, will greatly increase spike and kernel numbers and grain yield.

Metabolomic profiling of wheat genotypes resistant and susceptible to root-lesion nematode Pratylenchus thornei

2021 ◽  
Author(s):  
Md Motiur Rahaman ◽  
Rebecca S. Zwart ◽  
Thusitha W. T. Rupasinghe ◽  
Helen L. Hayden ◽  
John P. Thompson
Keyword(s):  
Root Lesion Nematode ◽  
Wheat Genotypes ◽  
Metabolomic Profiling ◽  
Pratylenchus Thornei ◽  
Lesion Nematode

Fine mapping of root lesion nematode (Pratylenchus thornei) resistance loci on chromosomes 6D and 2B of wheat

2019 ◽  
Vol 133 (2) ◽  
pp. 635-652 ◽  
Author(s):  
Muhammad Shefatur Rahman ◽  
Katherine J. Linsell ◽  
Julian D. Taylor ◽  
Matthew J. Hayden ◽  
Nicholas C. Collins ◽  
...  
Keyword(s):  
Fine Mapping ◽  
Root Lesion Nematode ◽  
Pratylenchus Thornei ◽  
Lesion Nematode

Crop rotation effect on wheat grain yield as mediated by changes in the degree of water and nitrogen co-limitation

2004 ◽  
Vol 55 (6) ◽  
pp. 599 ◽  
Author(s):  
Victor O. Sadras ◽  
Jeff A. Baldock ◽  
Jim W. Cox ◽  
W. D. Bellotti
Keyword(s):  
Grain Yield ◽  
Crop Rotation ◽  
Faba Bean ◽  
Inorganic Nitrogen ◽  
Wheat Yield ◽  
Tissue Expansion ◽  
Grain Protein Content ◽  
Stress Index ◽  
Nitrogen Stress ◽  
Stress Effect

Theoretically, growth of stressed plants is maximised when all resources are equally limiting. The concept of co-limitation could be used to integrate key factors affected by crop rotation. This paper tested the hypothesis that the effect of crop rotation on the yield of wheat is partially mediated by changes in the degree of co-limitation between nitrogen and water. Four rotations were established on a sodic, supracalcic, red chromosol in a Mediterranean-type environment of southern Australia. Rotations included wheat grown after (a) faba bean harvested for grain, (b) faba bean incorporated as green manure, (c) ryegrass pasture, or (d) medic pasture; barley was grown after wheat in all cases. The response of wheat to the rotations during 3 growing seasons was analysed in terms of nitrogen and water co-limitation, and the response of barley was taken as a measure of the persistence of rotation effects. Daily scalars quantifying water and nitrogen stress effects on tissue expansion were calculated with a crop simulation model. These scalars were integrated in a series of seasonal indices to quantify the intensity of water (SW ) and nitrogen stress (SN ), the aggregated intensity of water and nitrogen stress (SWN ), the degree of water and nitrogen co-limitation (CWN ), and the integrated effect of stress and co-limitation (SCWN 25 CWN/SWN ). The expectation is that grain yield should be inversely proportional to stress intensity and directly proportional to degree of co-limitation, thus proportional to SCWN . Combination of rotations and seasons generated a wide variation in the amount of water and inorganic nitrogen in the 1-m soil profile at the time of wheat sowing. Plant-available water ranged from 33 to 107 mm, and inorganic nitrogen from 47 to 253 kg N/ha. Larger amounts of nitrogen were found after green-manured faba bean, and smaller after grass pasture. There was a consistent effect of rotation on wheat yield and grain protein content, which persisted in subsequent barley crops. Measured grain yield of wheat crops ranged from 2.5 to 4.8 t/ha. It was unrelated to water or nitrogen stresses taken individually, inversely related to the aggregated stress index SWN , and directly related to the CWN index of co-limitation. The combination of stress and co-limitation in a single index SCWN accounted for 65% of the variation in measured crop yield. This is a substantial improvement with respect to the stress effect quantified with SWN , which accounted for 43% of yield variation. It is concluded that rotation effects mediated by changes in the relative availability of water and nitrogen can be partially accounted for by degree of resource co-limitation.

Effects of the root-lesion nematode, Pratylenchus thornei, on wheat yields in Mexico

Nematology ◽  
2004 ◽  
Vol 6 (4) ◽  
pp. 485-493 ◽  
Author(s):  
Julie M. Nicol ◽  
Ivan Ortiz-Monasterio
Keyword(s):  
Agronomic Traits ◽  
Wheat Yield ◽  
Sources Of Resistance ◽  
Nematode Density ◽  
Pratylenchus Thornei ◽  
Susceptible Control ◽  
Lesion Nematode ◽  
Northwestern Mexico ◽  
Field Plots ◽  
Negative Linear Relationship

Abstract Tolerance and resistance to P. thornei of seven CIMMYT-derived cultivars of wheat (Triticum aestivum), selected on soil naturally infested by Pratylenchus thornei and released from 1960-1997, were evaluated under optimum and limited irrigation conditions in northwestern Mexico. Replicated trials were grown in a naturally infested site in two seasons. Differences in yield, agronomic traits and nematode numbers were recorded in paired field plots, untreated or fumigated with dazomet to control nematodes. With optimum irrigation the nematode did not affect wheat yield but, with limited irrigation where plants were under water-stress, yield loss of all cultivars was comparable to that of the intolerant, susceptible control cv. Warigal (29%). There was a significant negative linear relationship (Y = –3.69 x + 3117) between initial nematode density (x) and grain yield (Y) under limited irrigation. None of these cultivars was resistant and post-harvest P. thornei populations had increased from three to 15 times the initial estimates. There was no relationship between date of release of cultivars and their responses to the nematode. There is a need for sources of resistance to be identified and incorporated into the germplasm.

Sign in / Sign up

Export Citation Format

Share Document