Root-knot nematode and Rhizoctonia solani affecting peanut in Texas /
Reproduction of Meloidogyne javanica (isolate no. 939) and an undescribed species of Meloidogyne (isolate no. 93-13a) was tested on Florunner and compared to that of M. arenaria (isolate no. 82-4) in greenhouse. The mean Rf (final population (Pf)/initial population (Pi)) values of M. javanica and 9...
| Main Author: | |
|---|---|
| Format: | Thesis Book |
| Language: | English |
| Published: |
[Place of publication not identified] :
[publisher not identified] ;
1997.
|
| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=739887611&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | Reproduction of Meloidogyne javanica (isolate no. 939) and an undescribed species of Meloidogyne (isolate no. 93-13a) was tested on Florunner and compared to that of M. arenaria (isolate no. 82-4) in greenhouse. The mean Rf (final population (Pf)/initial population (Pi)) values of M. javanica and 93-13a were similar, but lower (P<0.01) than that of M. arenaria. The relationship between the initial population densities (Pi) of the three Meloidogyne species and peanut yield was determined in microplots in 1995 and 1996. All three nematode species caused pod galling, which positively related to Pi (R2=0 .075, and 0.88 (P<0.01) in 1995 and 1996 respectively). Percentages of pods galled by M. javanica and 93-13a were similar but lower (P<0.01) than that caused by M. arenaria in both years. The relationship between Pi and pod yield fit a liner model. Yield slopes for arenaria and 93-13a were similar both years, and those of arenaria and M. javanica in 1995. The interspecific breeding line TxAG7, developed for resistance to M. arenaria, also was resistant to reproduction of M. javanica-and 93-13a. The gerplasmline TP-223, derived from TxAG7, was resistant to M. javanica and segregating for resistance to 93-13a. The interaction of M. javanica and R. solani (AG-4) caused synergistic or additive effects with respect to yield suppression of peanut, depending on inoculum densities of both pathogens. Rhizoctonia solani did not affect Rf of M. javanica. Pod or root infection by R. solani was enhanced by M. javanica (P<0.01). Resistance of TxAG7 to M. javanica was stable in the presence of R. solani. Imposing a water stress on peanut, 8 weeks after planting, did not affect the interaction of M. javanica and R. solani in field microplots. |
|---|---|
| Item Description: | Vita. "Major Subject: Plant Pathology". |
| Physical Description: | xvi, 121 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. Reproduction of Meloidogyne javanica (isolate no. 939) and an |
| Bibliography: | Includes bibliographical references: pages 105-120. |