Phenotypic characters associated with yield adaptation of wheat to a range of temperature conditions

Field Crops Research, 29 (1992) 69-77

69

Elsevier Science Publishers B.V., Amsterdam

Phenotypic characters associated with yield adaptation of wheat to a range of temperature conditions* N.A. MashiringwanP and M.A. Schweppenhauserb aCrop ,¢reedingInstitute, Department of Research and Specialist Servi~,.es, P~O. Box 8100, Causeway, Harare. Zimbabwe bDepartment of Crop Science, University of Zimbabwe, P.O. Box MP16 7, Mount Pleasant, Harare, Zimbabwe (Accepted 20 December 1990)

ABSTRACT Mashiringwani, N.A. and Schweppenhauser, M.A., 1992. Phenotypie characters associated with yield adaptation of wheat to a range of temperature conditions. Field Crop Res., 29: 69-77. The range of adaptation ofwheat (Triticum aestivum L. emmend. Thell.) is influenced by temperature variation. This study was aimed at determining phenotypic characters that are associated with yield adaptation of wheat to a range of temperature conditions experienced in Zimbabwe. Thirty genetically diverse lines of wheat were grown in a field experiment from 1984 to 1986 at seven locations that ranged in altitude from 421 to 1506 m, providing different temperature conditions. Analysis of variance, correlation matrices and regression analysis of grain yield using the mean maximum temperature during pre-anthesis at the locations in each year as the environmental index, were done. The lines were divided into four cla~ses of adaptation to temperature environments based on linear regression slopes and intercept, mean yield and estimated yield at the warmest environment. The regression slopes were negatively related (P<0.001) with grain filling duration and positively (P<0.01) with duration to anthesis. Differences in grain filling rate and grain weight per ear significantly (P < 0.01 ) explained line variation of yield across all temperature c~nditions. Lines classified as well adapted to all temperature conditions had the highest mean yield, 3rain filling rate and grain weight per ear. The improvement of grain filling rate and grain weight per ~:arwould appear to lead to increased grain yield of lines in all classes of adaptation, and wide adaptation to a range of temperature conditions. However, knowledge about the genetic basis of grain fiiling rate and/or grain weight per ear variation among lines is necessary for an effective and efficient use of these characters in breeding and selection for high yield across all temperature conditions.

INTRODUCTION

Adaptation is ~ state of fitness to a given environment (Gotoh and Chang, 1979). Finlay and Wilkinson (1963) divided adaptation into mean perform*Extracted from a thesis s~bmitted by the first author Jr. partial ffif~lment of the requirements for the M.Phil. degree, Department of Crop Science, Uriversi~y of Zimbabwe, 1988.

0378-4290/92/$05.00 @ 1992 Elsevier Science Publishers B.V. All rights reserved.

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N.A. MASHIRINGWANi AND M.A. SCHWEPPENHAUSER

ance and stability of performance. Wide adaptation refers to the level of response of a given line to a wide array of environmental conditions (Fi~lay and Wilkinson, 1963 ). Widely adapted cultivars with good economic yield are desired by most plant breeders (Eberhart and Russell, 1966; Finlay, 1968; Shebeski, 1974), because oi"the need for cultivars that can adapt to seasonal changes within small regions and marginal conditions in new areas that are opened up as crop area increases. Even under irrigated culture, where growing conditions may be considered favourable, shortages of irrigation water occur associated with ',he inability of farmers to match hectarage with water available in reservoirs (Mashiringwani and Harahwa, 1985 ). In Zimbabwe, the range of adaptation of wheat cultivars is influenced by temperature variation (Cackett and Wall, 1971; Mashiringwani, 1985 ). Generally, temperature increases with decline in altitude from the highveld to the lowveld (Mashiringwani, 1985 ). Resistances to low and high temperature are inversely related (Jensen, 1981 ). The mechanisms of adaptation to low and high temperature should therefore differ. Sullivan (1972) reported positive correlations between high temperature and drought tolerance in sorghum (Sorghum bicolor (L.) Moench). The mechanisms of resistance to high temperature may also involve escape, avoidance, tolerance and recovery. Thus the effect of high temperature a~ both ends of the season as in the lowveld of Zimbabwe may be avoided by the use of short duration cultivars. This stabilises year-to-year yields but the yields are relatively low because these cultivars cannot take advantage of the occasional longer season (Bagga and Rawson, 1977). The use of high-temperature-tolerant wheat cultivars (Kanani and Jadon, 1985 ) that are stimulated instead of being inhibited by high temperature increases (Weidner and Ziemens, 1975) and with longer duration would confer wide adaptation and higher productivity under stress conditions. In Zimbabwe, a significant linear ':on'elation was found between maximum temperatures in May (early ~owfh pel~cJd of wheat) and the number of fertile spikelets produced per ear of wheat (Cackett and Wall, 1971 ). These same authors also exam~r..cd and compared the major factors involved in yield determination at two locations (one of which has cool growing conditions and the other, warm conditions) and observed that leaf area index and leaf area duration were not important as yield determinants under local wheat growing conditions. The yield differences between ~,hetwo locations were accounted for by differences in grain number per ear and grain size. Grain size and yield were found to be dependent on the rate of grain dry matter accumulation in wheat (Van Sanford, 1985) and in various crops (Evans and Wardlaw, i 976; Fusseil and Pearson, 1978). High temperature during the early growth phases hasten ¢iifferentiation and result in early flowering, poor tillering (Kanani and Jadon, 1985 ), small ears and fewer grains per ear (S~sod':r. et al., ! 9~,), whil~ daring the grain filling stage it shortens the phase and reduces grain size (Cacket.~ and Wall, i 971;

PHENOTYPlC CHARACTERSASSOCIATEDWITH YIELD ADAPTATIONOF WHEAT

7!

Evans et al., 1975). A combination of these effects leads to reduced grain yield under high temperature. The breeding of stable cultivars is important in Zimbabwe where wheat is a high investment crop. A knowledge of the characters that contribute to high economic yield under a range of realistic climatic situations is a prerequisite in the development of such cultivars. The objective of this study was to determine phenotypic characters associated with yieId adaptation of wheat to a range of temperature conditions. MATERIALS AND METHODS

Experimental Thirty genetically diverse wheat lines that comprised sixteen Zimbabwean, ten Mexican, three Indian and one Israeli, and differed in yield potential, tillering capacity, grain size, earliness to flower or mature, ear size and plant height, were grown in a randomized block desi~n replicated three times in a field experiment at seven locations in Zimbabwe from 1984 to 1986. The locations, namely, Chiredzi (430 m above sea l~vel), Chisumbanje (421 m a.s.l.), Gwebi (1448 m a.s.l.), Harare (1506 m a.s.l.), Kadoma (1157 m a.s.l.), Matopos ( 1338 m a.s.l.) and Panmure (881 m a.s.l.), are representative of all wheat growing areas of the country. The experiment was planted during the month of May (the beginning of the winter season ) on a date most appropriate for each location. Fertilizer rates applied at each IGcation in each year were according to recommendations based on a chemical analysis done by the Chemistry and Soil Research Institute (Harare) on soil samples. Irrigation amounts applied were based on evapotranspiration ratios and irrigation schedules determined by Metelerkamp (1975). Daily maximum and minimum temperature records were kept at each location in each year during the growing cycle. The experiment at each location in each season was over-seeded to ensure uniform emergence and then thinned at 14 days from planting to leave a plant at every 5 cm mark to ensure uniform plant establishment across all plots. The gross plot size was six rows 20 cm apart and 4 m long and the net plot was four rows 3 m long. Days to anthesis and 50% physiological maturity, number of ears from 2C~plants, weight of grains from 20 plants, grain weight per net plot and grain moisture content were tauten from each plot. Grair~ weight per net plot was based on weight of grains from 20 plants. The 20 plants were randomly selected and tagged before heading. From the above, weight of grains per ear, grain filling duration, grain filling rate and grain yield ver hectare at 12.5% ~.ioi~'ture content were derived. Leaf rust, which usually occurs at the end of the growing season, was insigni~cantly low during the course of this study. All the lines used in the study were immune to local races of stem rust.

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N.A. MASHIRINGWANiAND M.A. SCHWEPPENHAUSER

Statistical analyses Analyses of variance were done to test for line, location and year differences for all plant characters and grain yield. Minimum, maximum and mean temperatures experienced during pre-anthesis, the anthesis period, post-anthesis and the complete growth period were correlated with grain yield at the 21 environments (7 locations X 3 years). Anthesis period at an environment was taken as 10 days, determined as 5 days before and after the average date of anthesis for the 30 lines at that environment. A modification of Finlay and Wilkinson's (1963) regression analysis was used to test for line differences in linear regression across the 21 environments. Based on the coefficients of correlation between the minimum, maximum and mean temperatures during preanthesis, anthesis, post-anthesis, and the complete growth period, and mean grain yield at the 21 environments, it was found that the maximum temperature during pre-anthesis (MAPR) explained most of the environmental variation in grain yield (r2= 0.8409, P < 0.001 ). Consequently, MAPR was used as the environmental index in the linear regression analysis. The slopes of linear regression were correlated with all the plant characters of the 30 lines. RESULTS

The location, location×year, genotype, genotypexlocation and genotype X location × year sources of variance had highly significant effects on grain yield ( P < 0.001 ). The significance of the location × year interaction effects on grain yield indicates that the 21 location × year combinations can be considered as separate environments. The mean maximum temperature during pre-anthesis (MAPR) across the 21 environments was negatively correlated with grain yield ( P < 0.001 ). The MAPR ranged from 2 I. 1 °C to 27°C. A test of homogeneity of 30 slopes of linear regressions ofgenotype mean yield over MAPR of wheat at 21 environments showed that the slopes were significantly different (P<0.001). The slope is a measure of the response of a genotype to temperature change. The slopes of linear regression and mean grain, yield of the 30 genotypes were inversely related (P<0.001). The genotype with the lowest regression coefficient of - 409 kg h a - ~ ° C - ~had the highest mean yield of 6905 kg h a - ~while the genotype with the highest coefficient of - 5 kg h a - i oC - ~ had the lowest mean yield of 4546 kg ha -~. Based c~ slopes of linear regression, mean yield, regression con~i :~atand estimated ~ield at lowest yielding environment, the genotypes were grouped into four adaptation classes (Table 1 ). Fouc genotypes were classified as specifically adapted to cool conditions, six to warm conditions, ten to all temperature conditions, while ten were poorly adapted to all temperature conditions. The phenotypic correlations of linear regression slopes with grain yield, days to anthesis and grain filling duration are shown in Table 2. The regression slopes were negatively related with grain

PHENOTYPICCHARACTERSASSOCIATEDWITHYIELDADAPTATIONOF WHEAT TABLE 1 Coefficients for linear regression equations and mean yields of 30 lines of wheat Line No.

Name

1 2 3 4 5 6 7 8 9 10 !i 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

F83066 $76003-6-4 Tokwe Sengwa SC79520-2-3 F82024 Angwa $78298-21-2 F83069 F83056 $78297-1-2 Chiwore F83068 SA79012-3-2 F83059 $78301-5-3 Gwebi SW791784-4-4 F81012-4 Tonm73 F83071 SC79371-6-3 F78006 Rusape $77021-7-4 F83067 Limpopo F78106 $75110-2-3 SC79358-9-1

Mean

Slope (kgha - I °C -~)

Intercept (kg/ha)

Estimated yield (kg/ha) a t 2 7 ° C

Mean yield (kg/ha)

Class of adaptation I

-115 -215 -371"* -409** -255* -103 -298* -249 -118 -182 -283* -299** -185 -364** -352** -268* -255* -198 -304** -275* -5 -236 -269* -324** -365** -229 -333** -127 -387** -231

8473 11556 15033 16722 12330 8143 13311 11678 18087 10098 13152 13737 10429 15048 14935 11835 12204 10475 14096 12708 4669 11517 12067 14612 15181 11150 14023 9065 15946 11245

5368 5751 5016 5679 5445 5362 5265 4955 4901 5184 5511 5664 5434 5220 5431 4599 5319 5129 5888 5283 4534 5145 4804 5864 5326 4967 5032 5636 54~7 5008

5707 6395 6120 6905 6216 5677 6155 5689 5254 5729 6362 6557 5989 6297 6479 540O 6087 571 l 6805 6105 4546 5840 5600 0~30 6422 5657 6013 6014 6642 5685

II II I III III II I IV IV IV I11 III II I I!I IV I1 IV III III IV IV IV III III IV I II III IV

-254

12624

5274

6030

*,**Slope significantly different from zero at the 5% and 1% level, respectively. [ = specificallyadapted to cool environments; II = specifically adapted to warm environments; III = well adapted to all environmems; and IV = poorly adapted to all environments.

filling duration and positively related with days to anthesis (P< 0.001 ). The duration of grain filling and days to anthesis of the genotypes ranged from 40 to 54 days and 76 to 100 days, respectively. Differences in grain filling rate and grain weight per ear significantly (P.< 0.01 ) explained genotypic variation of grain yield across all temperature conditions.

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N.A. MASHIRINGWANIAND M.A. SCHWEPPENHAUSER

TABLE 2

Relationship of linear regression slopes with grain yield, days to anthesis and grain filling duration of wheat Agronomic trait

Correlation coefficient

Grain yield

- 0.765*** 0.599*** - 0.656***

Days the anthesis

Grain filling duration

***Correlation coefficient significantly greater than zero at the 0.1% level of probability. TABLE 3

Mean performance of four yield adaptation classes of 30 lines of wheat Trait

Mead yield ( k g / h a ) Days to anthesis Days to maturity Grain filling duration (d~y) Grain filling rate (kg ha- t day -~ ) Grain weight per ear (g)

Class of adaptation

Mean

I

II

III

IV

6160 79 130 51 139.7 1.43

5911 86 ! 34 47 146.3 !.53

6537 81 132 50 150.3 1.59

5510 85 133 48 133.7 1.39

6029.5 83 132 49 142.5 1.49

~I= specifically adapted to cool envi;onments; It = specifically adapted to warm environments;

III =well adapted to all environments; and IV = poorly adapted to all environments.

The mean grain yield, days to anthesis and maturity, grain filling rate and grain weight per ear of four adaptation classes are shown in Table 3. Lines classified as well adapted to all temperature conditions had the highest mean yield, grain filling rate and grain weight per ear but the mean duration to maturity was intermediate. Those adapted to warm conditions had the longest duration to anthesis and maturity but the shortest duration of grain filling. Lines that showed poor adaptation to all temperature conditions had the lowest mean yield, grain filling rate and grain weight per ear. There was little difference in duration of grain filling among the poorly adapted genotypes and those adapted to warm conditions, but there were large differences in the grain filling rate and grain weight per ear. Genotypes with specific adaptation to cool environments had a low grain filling rate and the longest duration of grain filling which compensated for the low grain filling rate. The grain filling duration of this class and the well adapted class were virtually the same. Lines in the well adapted category and those with specific adaptation to coo! conditions showed temperature sensitivity, i.e., their linear regression slopes were

PHENOTYPIC CHARACTERS ASSOCIATED WITH YIELD ADAPTATION OF WHEAT

7~

significantly different from zero. Genotypes in the poorly adapted category and those with specific adaptation to warm conditions showed temperature insensitivity, i.e., their linear regression slopes were not significantly different f r o m zero. DISCUSSION

There is significant genetic variability for yield response to temperature in wheat. This agrees with Sisodia et al. (1978) and Kanani and Jadon (1985). Temperature sensitivity in wheat favours high mean yield, is associated with short duration of grain filling and indicates possible adaptation to all temperature conditions or specific adaptation to cool conditions. The two adaptation classes could however be differentiated by examining the rate of grain filling, grain weight per ear and duration to maturity of the genotypes. High grain filling rate and grain weight per ear and an intermediate duration to maturity are associated with high yield adaptation to a range of temperature conditions. The importance of the effect of the rate of grain filling on grain yield of wheat (Sofield et al., 1977; Jenner and Rathjen, 1978) and of soyabean (Salado-Navarro et al., 1986) has been reported for single environments but not across several environments. Similarly, there are reports of significant effects of grain weight per ear on grain yield of wheat (Kachur, 1988; Zhukov and Nikitina, 1988) in single environments only. Yield adaptation to cool conditions is characterised by a short duration to anthesis and maturity of the genotypes. Thus, increasing the rate of grain filling of the genotypes in this class without affecting the duration of grain filling would be the best strategy of improving yield adaptability to cool conditions similar to those that prevail in the highveld of Zimbabwe. An increase in the duration of grain filling would lead to exposure of later growth stages to high temperature that normally prevail towards the end of the growing season. A long duration to anthesis and short duration of grain filling have been shown to be associated with temperature insensitivity. Genotypes that show temperature insensitivity have low mean yield and could be either poorly adapted to all temperature conditions or specifically adapted to warm conditions. The genotypes that are adapted to warm conditions have higher grain weight per ear and grain filling rate that compensates for the short duration of grain filling. Lengthening the duration of grain filling ofgenotypes ~dapted to warm conditions as the grain filling rate is increased would irnpro:e yield in these environments. However, the shortness of their grain filling duration might be an adaptive response to warm conditions. !mproving grain filling rate and grain weight per ear would increase grain yield of genotypes in all classes of adaptation and hence lead to high yield and wide yield adaptation. However, the rate of grain filling is not easy for use in selecting in segregating populations because individual plants would have to be assessed, which is not

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N.A.MASHIRINGWAN!ANDM.A,~C~WEPPENHAUSER

siwple. In addition~ an understanding of the genetic basis ofgenotypic differences in grain filling rate and grain weight per ear is necessary for an effective and efficient use of these characters in breeding and selection for high yield across all temperature conditions. REFERENCES Bagga, A.K. and Rawson, H.M., 1977. Contrasting responses of morphologically similar wheat cultivars to temreratures appropriate to warm temperate climates with hot summers: A study in controlled environment. Aust. J. Plant Physiol., 4: 877-887. Cackett, K.E. and Wall, P.C., 1971. The effect of altitude and season length on the growth and yield of wheat (Triticum aestivum L.) in Rhodesia. Rhod. J. Agric. Res., 9:107-120. Eberhart, S.A. and Russell, W.A., 1966. Stability parameters for comparing varieties. Crop. Sci., 6: 36-40. Evans, L.T. and Wardlaw, I.F., 1976. Aspects of the comparative physiology of gram yield in cereals. Adv. Agron., 28:301-359. Evans, L.T., Wardlaw, I.F. and Fischer, R.A., 1975. Wheat. In: L.T. Evans (Editor), Crop Physi o l o g y - Some Case Studies. Cambridge University Press, Cambridge, pp. 101-147. Finlay, K.W., 1968. The significance of adaptation in wheat breeding. In: K.W. Finlay and K.W. Shepherd (Editors), Proceedings of the Third International Wheat Genetics Symposium, pp. 403-409. Finlay, K.W. and Wilkinson, G.N., 1963. The analysis of adaptation in a plant breeding programme. Aust. J. Agric. Res., 14: 742-754. Fussell, L.K. and Pearson, C.J., 1978. Cou,:se ofgrain development and its relationship to black region appearance in Pennisetum americanum. Field Crops Res., 1: 21-31. Gotoh, K. and Chang, T.T., 1979. Crop adaptation. In: J. Sneep, A.J.T. Hendriksen and O. Holbek (Editors), Plant Breeding Perspectives. Centre for Agriculture-Publishing and Documentation, Wageningen, Netherlands, pp. 234-261. Jenner, C.F. and Rathjen, A.J., 1978. Physiological basis of genetic differences in the growth of grains ofsix varieties of wheat. Aust. J. Plant Physiol., 5: 249-262. Jensen, S.D., 1981. Breeding plants for stress environments. In: K.J. Frey (Editor), Plant Breeding, II. Iowa State University Press, Ames, IA, p. 71. Kachur, O.T., 1988. Correlation of grain weight per ear and grain size with yield per plant in winter wheat. Wheat, Barley and Triticale Abstracts, 5: 1. Kanani, P.K. and Jadon, B.S., 1985. Variability for high temperature tolerance in bread wheat. Indian J. Agric. Sci., 55: 63-66. Mashiringwani, N.A., 1985. Response of wheat to temperature as influenced by altitude. In: E. Torres (Editor), Regional Wheat Workshop, Eastern, Central and Southern Africa, and Indian Ocean, Njoro, Kenya, 2-5 September 1985. Nakuru Press, Nakuru, Kenya, pp. 279283. Mashiringwani, N.A. and Harahwa, C., 1985 The response of twenty wheat (Triticum aesti?urn L..~-,~. Thell.) vafie~c~ ~,o ~;row~ag conditions ia Zimbabwe. Zimbabwe Agric. J., 82: 11-15. Metelerkamp, H.R.R., 1975. Irrigation scheduling by means of class "A" pan evaporation. Rhod. Agric. J., Tech. Bull., 16: 1-35. Salado-Navarro, L.R., Sinclair, T.R. and Hinson, K., 1986. Yield and reproductive growth of simulated and field-grown soyabean. II. Dry matter allocation and seed growth rates. Crop Sci., 26: 971-975. Shebeski, L.H., 1974. Early generv,tion selection for wide range adaptability in the breeding

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programme. In: Proceedings of the Fourth FAO/Rockefeiler FoundaTion Wheat Seminar, Tehran, 1973. FAO, Rome, pp. 160-167. Sisodia, N.S., Singh, K.P. and Sheopuria, R.R., 1978. Variability for high temperatures tolerance in wheat. In: S. Ramanujam (Editor), Proceedings Of The Fifth International Wheat Genetics Symposium, New Delhi, 23-28 February 1978, Vol. I: 216-224. Sofield, I., Evans, L.T., Cook, M.G. and Wardlaw, I.F., 1977. Factors influencing the rate and duration of grain filling in wheat. Aust. J. Plant Physiol., 4: 785-797. Sullivan, C.Y., 1972. Mechanisms of heat and drought resistance in grain sorghum and methods of measurement. In: N.G.P. Rao and L.R. House (Editors), Sorghum in the Seventies. Oxford and IBH, New Delhi, pp. 247-264. Van Sanford, D.A., 1985. Variation in kernel growth characters among soft red winter wheats. Crop Sei., 25: 626-630. Weidner, M. and Ziemens, C., 1975. Pre-adaptation of protein analysis in wheat seedlings to high temperature. Plant Physiol., 56: 590-594. Zhukov, V.I. aod Nikitina, V.I., 1988. Evaluating initial material by the principal component method. Wheat, Barley and Triticale Abstracts, 5: 1.