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CROP ECOLOGY, MANAGEMENT & QUALITY

Yield Components of Pearl Millet and Grain Sorghum across Environments in the Central Great Plains

Contribution of the Dep. of Agronomy and Horticulture, Univ. of Nebraska, Lincoln, NE 68583-0915

^* Corresponding author (smason1{at}unl.edu)

	ABSTRACT

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 
Location, year, and water supply influence the relationship between grain yield and yield components of pearl millet [Pennisetum glaucum (L.) R. Br] and grain sorghum [Sorghum bicolor (L.) Moench]. Field experiments were conducted in 2000 and 2001 on a silt loam soil in semiarid western Nebraska and on a silty clay loam soil in subhumid eastern Nebraska to determine how environment (location, year, water regime) influences number of panicles per square meter, kernel weight, and kernels per panicle in determining grain yield of pearl millet and grain sorghum. Grain yield components were examined by analysis of variance, correlation, and path analysis. Four water regimes were used: (i) no irrigation, (ii) single irrigation at boot stage, (iii) single irrigation at mid-grain fill, and (iv) multiple irrigations. Grain sorghum produced from 109 to 212 g m^–2 greater yield than pearl millet in all environments in western Nebraska and 52 to 150 g m^–2 greater yield in eastern Nebraska. Correlation and path analysis direct effects indicated that the number of kernels per panicle (R from 0.36–0.93; P from 0.21–0.45) and kernel weight (R from 0.46–0.89; P from 0.46–0.73) were associated with grain yield for both crops at both locations, but in the path analysis, kernel weight was more highly associated with grain yield for grain sorghum (P from 0.65–0.73) than the number of kernels per panicle (P from 0.21 and 0.32). Plant breeding and production research to increase pearl millet and grain sorghum yield should consider all yield components, but increased emphasis on kernel weight is merited for grain sorghum.

	INTRODUCTION

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 
YIELD DIFFERENCES in agronomic crops are associated with kernel number (the product of panicles per square meter and kernels per panicle) and kernel weight. Environmental factors such as temperature and available water influence yield components (Evans and Wardlaw, 1976). Potential for yield compensation occurs early in the plant life cycle through adjustment in the number of panicles per square meter and kernels per panicle. Variation in kernel weight allows for a degree of yield compensation late in the life cycle. Increases in kernels per panicle and in kernel weight may help compensate for low plant populations or limited tillering. As a result of this compensatory power, grain yield in cereals is relatively insensitive to plant population (Anderson, 1986); however, this compensation is less than perfect in grain sorghum (Kiniry, 1988) and pearl millet (Craufurd and Bidinger, 1989).

Eastin and Sullivan (1974) developed simple developmental stage terminology useful for yield and yield component analyses for grain sorghum on the basis of growth stage as follows: (i) the vegetative period from planting to panicle initiation (GS1); (ii) the reproductive period (GS2) from panicle initiation to flowering; and (iii) grain filling period (GS3) from flowering to physiological maturity. These three developmental stages were similarly described for pearl millet by Maiti and Bidinger (1981). For grain sorghum and pearl millet, potential kernel number is set during GS2 and kernel weight is determined within genetic limits during GS3 (Eastin et al., 1999; Maiti and Bidinger, 1981). Water or temperature stress during late GS1 and GS2 can reduce kernel number irreversibly and adequate water during grain fill can do little to ameliorate the loss in grain yield except for limited increase in kernel weight. During GS3, grain sorghum grain yield has been found to be less sensitive to water stress than during GS2, and the lower yield reduction was largely due to reduced kernel weight (Eastin et al., 1983). Yield component studies with grain sorghum have shown the number of panicles per square meter to be a yield component associated with yield changes from nonuniform stand reductions (Larson and Vanderlip, 1994), border effects in strip intercropping (Lesoing and Francis, 1999) and N application (Rajewski et al., 1991); kernels per panicle for weed competition (Limon-Ortega et al., 1998), nonuniform stand establishment (Larson and Vanderlip, 1994), row spacing and plant population (Stickler and Wearden, 1965; M'Khaitir and Vanderlip, 1992), delayed planting (M'Khaitir and Vanderlip, 1992), soil water storage differences (Norwood, 1992), and defoliation (Rajewski et al., 1991); and kernel weight for environmental differences (Heinrich et al., 1985; Saeed et al., 1986; Rajewski et al., 1991), row spacing and plant population (Stickler and Wearden, 1965), and soil water storage differences (Norwood, 1992). Yield component studies with pearl millet have shown the number of panicles per plant to be the yield component most associated with yield changes with plant population, but because of profuse tillering, the number of panicles per square meter may decrease (van Oosterom et al., 2002) or remain nearly constant (Carberry et al., 1985; M'Khaitir and Vanderlip, 1992) with increasing plant population. Panicles per square meter or panicles per plant is the yield component most often associated with grain yield grain yield differences due to preflowering water stress (Mahalakshmi and Bidinger, 1986); kernels per panicle for mid-season water stress (Bidinger et al., 1987), temperature (Ong, 1983), and weed competition (Limon-Ortega et al., 1998); and kernel weight for terminal water stress (Bidinger et al., 1987) and temperature (Ong, 1983).

Since yield components are interrelated, have compensatory effects, and develop sequentially at different growth stages, path coefficient analysis is often used to characterize yield component variations at the phenotypic and genotypic levels, and to identify plant breeding and/or crop management research priorities (Board et al., 1999) and expand physiological understanding of crop morphology (García del Moral et al., 2003). Path coefficient analysis provides more information among variables than do simple correlation coefficients since this analysis provides the direct effects of specific yield components on yield, and indirect effects via other yield components (García del Moral et al., 2003).

This research was conducted to determine the effect of environment (year, location, water regime) on the yield components of grain sorghum and pearl millet, with the hope of identifying the yield component(s) of pearl millet and grain sorghum most critical in Central Great Plains production environments. The research focus was on western Nebraska where this experiment was conducted to determine the potential for pearl millet and grain sorghum as crops. The eastern Nebraska location provided a reference point for a region where grain sorghum is widely grown. Our hypotheses were that environment would alter those yield components that are most closely associated with grain yield in pearl millet and grain sorghum, and that (i) under limited water stress, the number of panicles per square meter would be the most important yield contributor for both crops, (ii) since kernel number is set during GS2, irrigation at boot stage would create conditions making kernels per panicle the most important contributor to grain yield for both crops, and (iii) with irrigation at mid-grain fill, kernel weight would be the greatest contributor to yield for both crops.

	MATERIALS AND METHODS

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 
Field experiments were conducted in western and eastern Nebraska in 2000 and 2001. The western Nebraska experiment was conducted at the University of Nebraska High Plains Agricultural Laboratory located 8 km north of Sidney, NE (+41.2°, –130.0°, at 1317 m elevation). Soil at the site is a Keith silt loam (fine-silty, mixed, superactive mesic, Aridic Argiustoll), and its chemical properties are presented in Table 1. Available water capacities for the soil are 0.20 to 0.23 cm cm^–1 for the 0- to 25-cm depth, 0.18 to 0.22 cm cm^–1 for the 25- to 58-cm depth, and 0.20- to 0.22-cm cm^–1 for the 58- to 152-cm depth (Borchers and Hartung, 1997). Pearl millet and grain sorghum are not widely grown in this region at present but potential exists for production of both crops.

The treatment structure was a 4 x 2 factorial at both locations. Factor one consisted of four water regimes chosen to reflect the range of environments possible at both locations: (i) no irrigation, (ii) single irrigation at boot stage, (iii) single irrigation at mid-grain fill, and (iv) multiple irrigations. Factor two consisted of two crops: a pearl millet hybrid (68A x 086R) and an early maturing grain sorghum hybrid (DK 28E). These were the best-adapted hybrids available for the Sidney location on the basis of performance tests. The experimental designs were different at the two locations becaue of a difference in irrigation systems available at the two sites. At Sidney, where the irrigation system was a lateral-move system with drop-nozzle booms, the experiment was conducted as a randomized complete block design with four replications. Plot size was 9.1 m (12 rows 76 cm apart) wide and 9.1 m long with 3-m alleys between plots. At Mead, where a furrow irrigation system was used, the experiment was conducted as a randomized complete block design with a split-plot treatment arrangement and four replications. The whole plot treatments were four water regimes, and the split plot treatment was crop. Plot size was 6.8 m wide (nine rows 76 cm apart) and 9.1 m long.

At Sidney, both pearl millet and grain sorghum were no-till planted into wheat stubble on 8 June 2000 and 11 June 2001. At Mead, the experimental area was disked before planting. Pearl millet and grain sorghum were planted on 1 June 2000 and 18 June 2001. At Sidney, final plant stands were 11.2 ± 0.7 plants m^–2 for pearl millet and 11.3 ± 0.7 plants m^–2 for grain sorghum in 2000. In 2001 plants stands were 13.5 ± 1.1 plants m^–2 for pearl millet and 12.7 ± 1.1 plants m^–2 for grain sorghum. At Mead, plant stands were 17.6 ± 0.2 plants m^–2 for grain sorghum and 17.4 ± 0.3 plants m^–2 for pearl millet in both years. All plant populations were within the recommended range for both crops at these locations.

Weed management involved the use of herbicides, cultivation, and hand hoeing. At Sidney, propazine [6-chloro-N,N',-bis(1-methylethyl)-1,3,5-triazine-2,4-diamine] was applied pre-emergence at 1.12 kg ha^–1. At Mead, atrazine [(6-chloro-N-ethyl-N'-(1-methyl)-1,3,5-triazine-2, 4-diamine] was applied pre-emergent at 1.12 kg ha^–1. When pearl millet reached the three-leaf stage, atrazine at 0.6 kg ha^–1 plus 2.2 kg ha^–1 of metolachlor [2-chloro-(2-ethyl-6-methylphenyl)-(2-methoxy-1-methylethyl) acetamide] and 0.56 kg ha^–1 of bentazon [3-(1-methylethyl)-(1H)-2, 1,3-benzothiadiazin-4 (3H)-one 2,2-dioxide] were applied.

At Sidney, a neutron probe (Campbell Pacific 503 DR, Campbell Pacific, Pacheco, CA) was used to monitor soil water content on a weekly basis. For the multiple irrigation treatment, irrigation water was applied whenever available soil water fell below 70% of the available soil water holding capacity. Irrigation water was applied to bring the available soil water level to at least 80% of the available soil water capacity. Supplemental water applications were made in 25-mm increments with a 1-d interval between applications to avoid runoff. Multiple irrigation treatment received 305 and 102 mm supplemental water application and in 2000 and 2001. Boot stage supplemental irrigation treatment received 127 and 25 mm in 2000 and 2001. Grain fill irrigation received 127 and 76 mm supplemental water in 2000 and 2001. At Mead, the decision to irrigate in all irrigation treatments was based on physical observation of crop stress and soil water content using the feel method (USDA, 1998). Furrow irrigation was used, with flow rate being controlled by adjusting the irrigation pump speed and gate openings on the irrigation pipe. Irrigated plots at Mead were brought to field capacity with each irrigation.

Two central rows, 3 m long, were hand-harvested from each plot to determine grain yield, and yield components. Before harvest, the number of panicles per square meter were counted in the harvest area, then 10-panicle subsamples were randomly harvested before grain yield harvest from these two rows to determine kernels per panicle and kernel weight. These subsamples were threshed, counted, and weighed separately from the rest of the harvest area, and the weights were added back for determination of grain yield. Grain from the 10-panicle subsamples were counted, weighed and corrected for water content to determine number of kernels per panicle and kernel weight. Grain yield and yield components were corrected to 140 g kg^–1 water content by drying at 60°C for at least 48 h.

Analyses of variance for grain yield and each yield component was conducted by the Mixed Models procedure of the SAS package as presented by Littell et al. (1996) and pooled across years since variances were similar on the basis of the F ratio test. Analyses were not combined across locations because of the use of different treatment arrangements, irrigation methods, plant populations, and the widely contrasting climatic conditions. Mean separation was done by PROC Mixed LSMeans P difference. Year, location, hybrid, and water treatments were all considered to be fixed effects.

Pearson correlations among yield and yield components were calculated using replicate values. Direct path coefficients (P) were determined with the CALIS procedure of SAS (SAS Inst., 1994) using the model proposed by Dofing and Knight (1992)(Fig. 1) . Because of limited number of water regime observations, path analysis was conducted across water regimes only, giving n = 28 at Sidney and n = 32 at Mead. Correlation and path analyses data were presented following the method used by García del Moral et al. (2003).

View larger version (13K): [in this window] [in a new window]   Fig. 1. Path diagram for the three yield component variables X1, X2, and X3 and grain yield as the response variable (Y), where Y = P1 + P2X2 + P3X3 + U3; X3 = P13X1 + P23X2 + U2; X2 = P12X1 + U1.

	RESULTS AND DISCUSSION

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

Yield and Yield Components
Year x Crop Interactions
Grain yields for pearl millet and grain sorghum were lower in the more stressful, shorter growing season environments at Sidney than at Mead and in the more stressful year 2000 than 2001 (Tables 3 and 4). Grain yield was higher for both crops at both locations in 2001 than in 2000, but the grain yield increase was greater for grain sorghum than pearl millet. In 2000 and 2001, average pearl millet grain yields were 85 and 82% of sorghum grain yields at Mead, while pearl millet yields were 51 and 76% of sorghum grain yields at Sidney. These lower pearl millet yields across environments as compared with grain sorghum confirm a recent report (Palé et al., 2003) that pearl millet does not have at present, adequate grain yield potential to replace grain sorghum as a grain crop in the Central Great Plains.

Correlations
Pearl millet and sorghum grain yields were correlated with kernels per panicle and kernel weight for both crops at both locations and also with panicles per square meter for grain sorghum at Sidney (Table 5). These results for grain sorghum are generally consistent with those of Rajewski et al. (1991), although they found kernel weight to have a higher correlation with yield than kernels per square meter. Saeed et al. (1986) found that the number of kernels per panicle was the major contributing factor to grain sorghum yield across dryland production environments, but the relative importance of kernel weight increased with increasing night temperature. Heinrich et al. (1985) concluded that grain sorghum kernel weight contributed to yield stability in low-yield environments and should be an objective of a breeding program for low input agriculture, while in this study, the correlation of kernel weight with grain yield was higher for the high yield environment at Mead. The pearl millet kernels per panicle association with grain yield is similar to those found by van Oosterom et al. (2002), while the kernel weight association with grain yield was similar to that reported by Bidinger et al. (1987) but contrasted with results of Carberry et al. (1985) who found kernel weight to be relatively constant.

Path Analysis
Model multiple correlations across water regimes indicated that the model used accounted for most of the grain yield variation at Sidney but only approximately 50% of the variation at Mead (Table 6). Direct effects were found for kernels per panicle and kernel weight to grain yield for both crops, but kernel weight direct effects were much larger for grain sorghum than for pearl millet. A direct effect for panicles per square meter to grain yield was found at Mead for both crops but was negative for pearl millet and positive for grain sorghum. This suggests that pearl millet, which prolifically tillers (Egharevba, 1977; Mahalakshmi and Bidinger, 1986), had an excessive number of tillers that produced panicles in this low stress environment and reduced yield, while sorghum grain yield would have benefited from a greater number of tillers producing panicles. Egharevba (1977) found that reducing pearl millet productive tillers per plant from 10 to 3 or 5 increased grain yield by 15 to 30%. Limited yield compensation was found in this study, as indicated by the small number of indirect effects present. However, grain sorghum indirect effects were found for number of panicles per square meter via kernel weight for sorghum grain yield, which was positive at Sidney and negative at Mead. For pearl millet, indirect effects for grain yield were found only for kernels per panicle via kernel weight at Sidney, similar to results of Ong and Monteith (1985).

Crop x Water Regime Interactions
Pearl millet grain yield was not increased by a single irrigation at the boot stage at either location (Tables 3 and 4), while a 67 and 119% increase in response to single irrigation at mid-grain fill, and multiple irrigations treatments was found at Sidney. At Mead, a single irrigation at mid-grain fill and multiple irrigations increased grain yield approximately 10%. Single irrigations at the boot or mid-grain-fill stages increased grain sorghum yields approximately 50% at Sidney and 15% at Mead, while multiple irrigations increased grain yield by 100% at Sidney and 27% at Mead. Grain yield responses of both crops to multiple irrigations was similar at Sidney, while grain sorghum had a greater grain yield increase at Mead. Sorghum grain yield responded similarly to single irrigation at either the boot or mid-grain fill stages, while pearl millet grain yield responded only to the mid-grain fill irrigation.

Pearl millet grain yield increase to multiple irrigations at Sidney was accompanied by increases in all yield components although the kernel weight increase was less than for other yield components, but at Mead, it was accompanied only with an increase in the number of kernels panicles^–1 (Tables 3 and 4). In contrast, sorghum grain yield increase to multiple irrigations at both locations was accompanied by increases in all yield components, with the increase in number of kernels per panicle being less than other yield components at Sidney.

Single irrigations had little effect on pearl millet yield components at Mead (Table 4). In contrast at Sidney, a single irrigation at the boot increased the number of panicles per square meter and kernels panicle, and single irrigation at mid-grain fill increased all yield components (Table 4). For grain sorghum, a single irrigation at boot increased the number of grain sorghum panicles per square meter and kernel weight, while mid-grain fill irrigation increased kernel weight at both locations (Tables 3 and 4), and the number of kernels per panicle at Mead. Delayed timing of irrigation generally had a greater effect on kernel weight and less effect on the number of panicles per square meter as expected (Eastin and Sullivan, 1974; Maiti and Bidinger, 1981; Norwood, 1992).

Year x Water Regime Interactions
Because of the large differences in the Sidney seasonal precipitation in 2000 and 2001 (Tables 1 and 2), grain yield response to irrigation treatments was much greater in 2000 than in 2001. The increase in average grain yield of the two crops in 2001 was accompanied by changes in kernel weight, while in 2000 all yield components increased. A single irrigation at boot and multiple irrigations increased panicles per square meter more than other yield components, while a single irrigation at the mid-grain fill stage increased all yield components similarly.

	CONCLUSIONS

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 
These results show that grain sorghum has higher yield potential than pearl millet across the diverse environments studied. Sorghum grain yield increased more in response to irrigation than did pearl millet, but pearl millet was more sensitive to environmental differences due to year and location. Grain sorghum number of panicles per square meter and kernel weight responded to irrigation more than pearl millet, while the response of number of kernels per square meter response for both crops were similar. Correlations of grain yield with yield components indicated that the number of kernel per panicle and kernel weight were associated with grain yield, but path correlation direct effects indicated that this association for grain sorghum was greater for kernel weight. Since the grain sorghum and pearl millet hybrids use in this study were the best available for western Nebraska, it is concluded that plant breeding and production research to increase pearl millet and grain sorghum yield in the Central Great Plains should emphasize all yield components, but kernel weight merits increased attention in grain sorghum.

	ACKNOWLEDGMENTS

 
We appreciate research technical assistance provided by Tom Galusha for the experiment conducted at Mead, and by Rob Higgins for the experiment at Sidney. We acknowledge the valuable assistance of Dr. Kent Eskridge, Department of Statistics, University of Nebraska, Lincoln, NE, with the data analysis used in this paper, and to Drs. Max Clegg and Charles Francis for critical review of the manuscript.

	NOTES

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 
Paper No. 14192 of the Journal Series of the Nebraska Agric. Res. Div. Research Supported in part by the Anna Elliot Fund, Univ. of Nebraska Foundation, and USAID Grant no. DAN 1254-G-0021 through INTSORMIL, the International Sorghum and Millet Collaborative Research Program.

Received for publication July 30, 2003.

	REFERENCES

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 

• Anderson, W.K. 1986. Some relationships between plant population, yield components and grain yield of wheat in a Mediterranean environment. Aust. J. Agric. Res. 37:219–233.
• Bidinger, F.R., V. Mahalakshmi, and G.D.P. Rao. 1987. Assessment of drought resistance in pearl millet [Pennisetum americanum (L.) Leeke]. I. Factors affecting yield under stress. Aust. J. Agric. Res. 38:37–48.
• Board, J.E., M.S. Kang, and B.G. Harville. 1999. Path analyses of the yield formation for late-planted soybean. Agron. J. 91:128–135.[Abstract/Free Full Text]
• Borchers, G.A., and S. Hartung. 1997. Soil survey of Cheyenne County. U.S. Gov. Print. Office, Washington, DC.
• Carberry, P.S., L.C. Campbell, and F.R. Bidinger. 1985. The growth and development of pearl millet as affected by plant population. Field Crops Res. 11:193–205.
• Christensen, N.B., R.L. Vanderlip, and G.A. Milliken. 1987. Response of pearl millet to grain sorghum environments. Field Crop Res. 16:337–348.
• Craufurd, P.Q., and F.R. Bidinger. 1989. Potential and realized yield in pearl millet (Pennisetum americanum) as influenced by plant population density and life cycle duration. Field Crops Res. 22:211–225.
• Dofing, S.M., and C.W. Knight. 1992. Alternate model for path analysis of small-grain yield. Crop Sci. 32:487–489.[Abstract/Free Full Text]
• Eastin, J.D., and C.Y. Sullivan. 1974. Yield consideration in selected cereals. p. 871–877. In R.L. Bielski et al. (ed.) Mechanisms of regulation of plant growth. Bull. 12. Royal Soc. of New Zealand, Wellington, New Zealand.
• Eastin, J.D., R.M. Castleberry, T.J. Gerik, J.H. Hulquist, V. Mahalakshmi, V.B. Ounguela, and J.R. Rice. 1983. Physiological aspects of high temperature and water stress. p. 91–112. In C.D. Raper, Jr., and P.J. Kramer (ed.) Crop reaction to water and temperature stresses in humid, temperate climates. Westview Press, Boulder, CO.
• Eastin, J.D., C.L. Petersen, F. Zavala-Garcia, A. Dhopte, P.K. Verma, V.B. Ounguela, M.W. Wit, V. Gonzalez Hernandez, M. Livera Munoz, T.J. Gerik, G.I. Gandoul, M.R.A. Hovney, and L. Mendoza Onofre. 1999. Potential heterosis associated with developmental and metabolic processes in sorghum and maize, p. 205–229. In J.G. Coors and S. Pandey (ed.) The genetics and exploitation of heterosis in crops. ASA, CSSA, and SSSA, Madison, WI.
• Egharevba, P.N. 1977. Tiller number and millet grain productivity. Cereal Res. Commun. 5:235–247.
• Evans, L.T., and I.F. Wardlaw. 1976. Aspects of the comparative physiology of grain yield in cereals. Adv. Agron. 28:301–359.
• Garrity, P.D., C.Y. Sullivan, and D.G. Watts. 1983. Moisture deficits and grain sorghum performance: Drought stress conditioning. Agron. J. 75:997–1004.[Abstract/Free Full Text]
• García del Moral, L.F., Y. Rharrabti, D. Villegas, and C. Royo. 2003. Evaluation of grain yield and its components in durum wheat under Mediterranean conditions: An ontogenic approach. Agron. J. 95:266–274.[Abstract/Free Full Text]
• Heinrich, G.M., C.A. Francis, J.D. Eastin, and M. Saeed. 1985. Mechanisms of yield stability in sorghum. Crop Sci. 25:1109–1113.[Abstract/Free Full Text]
• Kerl, D.E., M. Babcock, and G. Halstead. 1982. Soil survey of Butler County, Nebraska. U.S. Gov. Print. Office, Washington, DC.
• Kiniry, J.R. 1988. Kernel weight increase in response to decreased kernel number in sorghum. Agron. J. 80:221–226.[Abstract/Free Full Text]
• Larson, E.J., and R.L. Vanderlip. 1994. Grain sorghum yield response to nonuniform stand reductions. Agron. J. 86:475–477.[Abstract/Free Full Text]
• Lesoing, G.W. and C.A. Francis. 1999. Strip intercropping effects on yield and yield components of corn, grain sorghum, and soybean. Agron. J. 91:807–813.[Abstract/Free Full Text]
• Limon-Ortega, A., S.C. Mason, and A.R. Martin. 1998. Production practices improve grain sorghum and pearl millet competitiveness with weeds. Agron. J. 90:227–232.[Abstract/Free Full Text]
• Littell, R.C., G.A. Milliken, W.W. Stroup, and R.D. Wolfinger. 1996. SAS system for mixed models. SAS Institute, Cary, NC.
• Maiti, R.K., and F.R. Bidinger. 1981. Growth and development of pearl millet plant. ICRISAT Res. Bull. 6. Hyderabad, India.
• Mahalakshmi, V., and F.R. Bidinger. 1986. Water deficit during panicle development in pearl millet: Yield compensation by tillers. J. Agric. Sci. (Cambridge) 1986:113–119.
• M'Khaitir, Y.O., and R.L. Vanderlip. 1992. Grain sorghum and pearl millet response to date and rate of planting. Agron. J. 84:579–582.[Abstract/Free Full Text]
• Norwood, C.A. 1992. Tillage and cropping system effects on winter wheat and grain sorghum. J. Prod. Agric. 5:120–126.
• Ong, C.K. 1983. Response to temperature in a stand of pearl millet (Pennisetum typhoides): Final number of spikelets and grains. J. Exp. Bot. 34:337–338.[Abstract/Free Full Text]
• Ong, C.K., and J.L. Monteith. 1985. Response of pearl millet to light and temperature. Field Crops Res. 11:141–160.
• Palé, S., S.C. Mason, and T.D. Galusha. 2003. Planting time for early-season pearl millet and grain sorghum in Nebraska. Agron. J. 91:1047–1053.
• Rajewski, J., C.A. Francis, and J.D. Eastin. 1991. Differential responses to defoliation of grain sorghum yield components and yield related traits. Crop Sci. 31:561–567.[Abstract/Free Full Text]
• Saeed, M., C.A. Francis, and M.D. Clegg. 1986. Yield component analysis in grain sorghum. Crop Sci. 26:346–351.[Abstract/Free Full Text]
• SAS Institute. 1994. SAS/STAT user's guide Version 6, fourth ed. SAS Inst., Cary, NC.
• Stickler, F.C., and S. Wearden. 1965. Yield and yield components of grain sorghum as influenced by row width and stand density. Agron. J. 57:564–567.[Abstract/Free Full Text]
• United States Department of Agriculture. (USDA-NRCS). 1998. Estimating soil moisture by feel and appearance. Program Aid Number 1619. Washington, DC.
• van Oosterom, E.J., G.J. O'Leary, P.S. Carberry, and P.Q. Craufurd. 2002. Simulating growth, development, and yield of tillering pearl millet. III. Biomass accumulation and partitioning. Field Crops Res. 79:85–106.

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