European Journal of Agronomy 13 (2000) 27 – 37
Seed quality of sweet white lupin (
Lupinus albus
) and
management practice in eastern Canada
M.A. Faluyi
a, X.M. Zhou
c, F. Zhang
b, S. Leibovitch
b, P. Migner
b,
D.L. Smith
c,*
aDepartment of Botany,Ondo State Uni6ersity,P.M.B. 5363,Ado-Ekiti, Nigeria
bBios Agriculture Incorporated,21,111 Lakeshore Road,PO Box 187,Ste. Anne de Belleu6e,Quebec, Canada,H9X 3V9 cDepartment of Plant Science,Macdonald Campus of McGill Uni6.,21111 Lakeshore Road,Ste. Anne de Belle6ue,
Quebec, Canada,H9X 3V9
Received 2 November 1999; received in revised form 25 February 2000; accepted 6 March 2000
Abstract
White lupin (Lupinus albus) has shown considerable yield potential as a spring-sown grain legume in eastern Canada and the northern USA. However, the effects of agronomic factors on seed protein and oil of white lupin cultivars have not been quantified under such short growing season conditions. The objective of this research was to determine appropriate management practices for production of better quality sweet white lupin. A 2-year study was conducted in eastern Canada to determine the responses of seed protein and oil in two large-seeded white lupin cultivars (Primorski and Ultra) to management factors. The two lupin cultivars were factorially combined on two soil types, with two planting dates and two row spacings. Of the 2 years, 1991 was more or less typical for the region, while 1992 was unusually cool and rainy. Both lupin protein and oil concentrations were not affected by the tested management factors over three of the 4 location years, except that the early planting date decreased the protein concentration of seeds in pods formed on the stem. The protein yield of seeds in pods formed on the branches was more sensitive to management factors in both sites in 1991. Total protein and oil yields of Ultra were higher than those of Primorski in the typical year (1991), but not in the atypically cool year (1992). On average, protein and oil yields were 59 and 93% higher, respectively, under the cooler climate conditions of 1992 than in 1991. The seed protein:lipid ratio in white lupin seeds was:4:1 and 3:1 in 1991 and 1992, respectively. In general, early planting in
narrow rows resulted in the highest yields of both protein and oil. © 2000 Elsevier Science B.V. All rights reserved.
Keywords:Lupinus albus; Sweet white lupin; Management practices; Seed quality; Oil; Protein
www.elsevier.com/locate/eja
1. Introduction
Large seeded sweet white lupin, like many other legume crops, has potential as a source of nutri-tion, particularly protein and oil, for livestock feed (Lopez-Bellido and Fuentes, 1986) and is a
* Corresponding author. Tel.: +1-514-3987851, ext. 7886; fax: +1-514-3987897.
E-mail address:[email protected] (D.L. Smith)
M.A.Faluyi et al./Europ.J.Agronomy13 (2000) 27 – 37 28
source of low-cost protein that can be profitably utilized to supplement protein inadequacies in cereals. As a N2 fixing legume, it can also play a role in enhancing soil fertility.
Williams (1979) observed that weather condi-tions, cultivation management, soil nitrogen status, and use of fertilizers accounted for about 95% of the variance in the protein content of wheat and concluded that the amount of protein incorporated into wheat kernels was controlled, to a considerable extent, by environmental factors. In addition, seed oil deposition is known to be affected by a range of agronomic factors (Canvin, 1965; Zhang et al., 1993, 1994). Shaw and Liang (1966) and Stone and Turker (1969) found that maximum protein con-centration occurred in soybean seed when the crop was water stressed during the pod filling stage. Stone and Turker (1969) also noted that severe moisture stress during pod filling adversely affected both the oil and protein yield of soybean. Rose (1988) observed that the degree to which these two economic traits were affected by water stress de-pended on the soybean genotype. High soil nitro-gen had adverse effects on seed oil concentration, but increased the crude protein concentration of sesame seed from 21.5 to 25.0% (Weiss, 1983).
White lupin has potential as a spring-sown grain legume in eastern Canada and the northern USA (Putnam et al., 1992). Seed yields of some cultivars have ranged from 2.5 to 4.0 t ha−1(Faluyi et al., 1997). Therefore, in eastern Canada there has been considerable interest in lupin. The effects of agro-nomic practices on seed protein and oil of white lupin cultivars have not been quantified under such short growing season conditions. The objective of this research project was to determine appropriate management practices for production of better quality sweet white lupin in eastern Canada by evaluating the effects of planting date, row spacing, and soil type on the seed protein and oil levels of two lupin cultivars.
2. Materials and methods
2.1. Experimental sites and procedures
The study was conducted on a fertile sandy-loam
(Typic, Melanic, Borunisol, Dystric, Eutrochrept) and a well drained clay-loam soil (Gleyed, Luvizol, aquic Hapludalf) at the E.A. Lods Agronomy Research Centre, McGill University, Ste. Anne de Bellevue, Quebec, Canada, during the 1991 and 1992 crop growing seasons. In each year, two sites that had not previously produced lupin were used for the experiments. Each site was fall-ploughed and subjected to secondary harrowing prior to planting in the spring.
The experimental design was a 2×2×2 factorial arranged in a randomized complete block with four replications; all factors were considered fixed ef-fects. The factors were cultivar (Ultra and Pri-morski), row width (20 and 40 cm) and planting date (early and late). In 1991, two lupin cultivars were planted on May 1 (sandy-loam) and May 4 (clay-loam) for the early planting date while May 14 (sandy-loam) and May 15 (clay-loam) were the late planting dates. In 1992, May 1 and 12 were early planting date and late planting dates, respec-tively, for both soil types. The two genotypes of white lupin were selected because they are reported to have satisfactory seed yields under Canadian conditions. The plot size was 9.6 m2
(4.0×2.4 m). The plots were seeded with 50 viable seeds m−2
. To ensure that nitrogen (N) was not limiting, the seeds were inoculated with commercialRhizobium lupini(Urbana Laboratories, St. Joseph, Montana) before planting. As the fields had not previously grown lupin, the inoculation rate used was 454 g 50 kg−1seed, double the recommended rate. Weed control was by hand and as necessary.
2.2. Data collection
A few days prior to harvest, ten plants were randomly selected from the central region of each plot. After drying, seeds from each plant were ground to pass a 1-mm screen with a Cyclone Mill (Udy, Fort Collins, CO) then dried to a constant weight at 70°C.
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mined by the Kjeldahl method (protein) using the Tecator Kjeltec system (Tecator AB, Hoganas, Sweden) and the Soxlet method (oil) using the Tecator Soxtec system (Tecator AB, Hoganas, Sweden), respectively (Zhang and Smith, 1994). Kjeldahl nitrogen values were multiplied by 6.25 to obtain crude protein values (Panford et al., 1988). Seed protein content was calculated as the amount of protein (mg) seed−1
(protein concen-tration times individual seed weight) and protein yield in g plant−1 and kg ha−1 (protein concen-tration times seed weight). Seed oil content and yield were estimated as for protein.
2.3. Statistical analyses
All data were analyzed by analysis of variance (SAS Institute Inc., 1988) and all significant main effects and interactions were considered. Because experimental errors were not homogenous over years, the data for each year are presented separately. When analysis of variance indicated significant effects, a least significant difference
(LSD) test was used to detect differences
between means (Steel and Torrie, 1980). Because most of the variables investigated in this study were not different between soil types, the few main effects of soil type, and interactions involving soil type, when they occurred, are de-scribed in the text rather than being shown in tables.
3. Results
3.1. Climate conditions
In 1991, climatic condition during the growing season (May – September) were more typical of the region than 1992. Rainfall in 1992 was higher than 1991 and the 30-year average. Temperatures were also much lower in 1992 than 30-year aver-age (Fig. 1). In 1991, the white lupin crops were subjected to moisture stress at various stages of their growth and development as the rains were not evenly distributed during the crop develop-ment period. In 1992, cooler weather was accom-panied by better distribution of precipitation. Also in 1991, the frequency and quantity of pre-cipitation were lowest during the month of June (59 mm) which corresponded with the time of flowering and onset of pod filling of the lupin crops. Flowering on the main stem raceme oc-curred between June 12 and 19 but rainfall was only 0.4 mm between June 1 and 11, and there was no rainfall between June 18 and 26 in that year. Thus, there was water stress before flower-ing, at anthesis and during pod filling in 1991. In 1992, total rainfalls for June and July were 80 and 143 mm, respectively, and flowering and onset of pod filling occurred within this period (Faluyi et al., 1997).
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3.2. Seed yield
Seed yield data was presented in an earlier paper (Faluyi et al., 1997). A brief summary of this provided here to allow better understanding of some of the oil and protein yield data. Early planting resulted in larger yields than later plant-ing in both years (Faluyi et al., 1997). However, this effect was larger in 1991 than 1992. Early planting of Ultra increased seed yield by 31 and 65% on clay and sandy loam soils, respectively, relative to late planting whereas early planting did not increase the seed yield of Primorski in 1991. Averaged over both cultivars, early planting in-creased seed yield by 11 and 19% on clay and sandy-loam soils, respectively, while yield was in-creased by 9 and 10% in the narrow row spacing compared with the wide row spacing, respectively in 1992. For instance, in 1991 on clay loam soil the yield of Ultra was increased by 31% due to early planting, but only 12% in 1992 (Faluyi et al., 1997).
When averaged over cultivars, soil types, and planting dates, yields were higher (10%) for plants produced in 20 cm rows than for plants produced in 40 cm rows (Faluyi et al., 1997), and this effect occurred across all treatments and in both years.
3.3. Protein yield and yield components
During the two-year study, the seed protein concentrations of main stem and branch seeds were not different between cultivars or row spac-ings on both soil types (Tables 1 – 4). The average values of protein concentrations across cultivars over time were 38.2 and 37.2 mg g−1, for the
seeds in pods formed on the stem and
branches, respectively. Over row spacing and time, the average values of protein concentrations were 38.1 and 37.2 mg g−1
for seeds in pods formed on the stem and branches, respectively. Late planting resulted in an increase in seed
protein concentration of main stem and
branch seeds on sandy-loam soil only in 1991 (Table 1).
The stem or branch protein yields of the culti-var Primorski were generally higher than Ultra.
Early planting increased branch protein yield by 49% in 1991 compared to late-planting. In con-trast, late-planting increased the same variable by 28% in 1992. During the 2 years of the study, row spacing had no effect on stem protein yield for both soil types (Tables 1 – 4) but the wider row spacing (40 cm) slightly increased branch protein yield on clay soil in 1991 (Table 2).
Total protein yield varied between the cultivars and was affected by planting date in 1991 (Tables 1 and 2). In 1991, Ultra, on sandy loam soils, had 49% higher total protein yields, respectively, than Primorski (Table 1). Total protein yield of plants seeded early and grown on clay-loam soil was 15% greater than that of those seeded late on the same soil type in 1991 (Table 2). In 1992, none of the tested factors affected the total protein yield at sandy or clay-loam sites (Tables 3 and 4). Averaged over row spacings and cultivars, the total protein yield was 18% greater for early than
for late-planted plants, while the branch
protein yield of early-planted plants was 168% higher than that of late-planted plants, although no difference existed in main stem protein yield on sandy-loam soil in 1991 (Table 1). On the clay-loam soil in 1991, early-planting in-creased the total seed protein yield by 15%, while the branch seed protein yield was 54% higher for early than late-seeded plants (Table 2). However, this was not the case at either site in 1992.
3.4. Oil yield and yield components
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Table 1
The effects of cultivars and planting date on sweet white lupin seed quality and its components on sandy-loam soil in 1991
Oil variables Protein variables
Management factors
BPY SGOC BGOC SOY BOY
SPY TOY
BGPC TPY
SGPC
(mg plant−1)
(t ha−1) (mg plant−1)
(mg plant−1) (mg plant−1) (mg g−1) (t ha−1)
(mg g−1) (mg g−1)
(mg g−1)a
Culti6ar
8.5a 9.1a 0.57b
39.0a 2.63b 0.06b 0.24a
39.3ab
Ultra 0.11b 1.07a
8.4a 8.5b 0.81a
Primorski 40.0a 39.8a 3.70a 1.40a 0.72b 0.33a 0.15b
Planting date
8.5a 8.8a 0.74a
36.9b 3.31a 0.26a 0.23a
37.8b
Early 1.10a 0.97a
0.82a
41.5a 41.8a 3.12a 0.41b 8.4b 8.8a 0.63a 0.14b 0.16b
Late
Row spacing
0.92a
39.8a 39.6a 3.25a 0.66a 8.4a 8.8a 0.69a 0.20a 0.20a
20 (cm)
8.5a 8.8a 0.68a 0.19a 0.19a
0.87a
39.1a 3.19a 0.85a
40 (cm) 39.6a
aSGPC, stem seed protein concentration (mg g−1); BGPC, branch seed protein concentration (mg g−1); SPY, stem seed protein yield (mg plant−1); BPY, branch seed protein yield (mg plant−1); TPY, total protein yield (t ha−1); SGOC, stem seed oil concentration (mg g−1); BGOC, branch seed oil concentration (mg g−1); SOY, stem seed oil yield (mg plant−1); BOY, branch seed oil yield (mg plant−1); TOY, total seed oil yield (t ha−1).
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Table 2
The effects of cultivar, planting date and row spacing on sweet white lupin seed quality and its components on clay-loam soil in 1991a
Oil variables Protein variables
Management factors
BPY SGPC BGPC SOY BOY
SPY TOY
BGPC TPY
SGPC
(mg plant−1)
(t ha−1) (mg plant−1)
(mg plant−1) (mg plant−1) (mg g−1) (t ha−1)
(mg g−1) (mg g−1)
(mg g−1)b
Culti6ar
9.0a 9.3a 0.73b
37.3a 3.06b 0.09b 0.25a
37.5a
Ultra 0.15b 1.03a
8.9a 9.2a 0.83a
Primorski 37.8a 36.8a 3.51a 0.84a 0.83a 0.19a 0.20b
Planting date
8.9a 9.4a 0.83a
35.8a 3.50a 0.16a 0.24a
37.5a
Early 0.60a 0.99a
0.86b
37.8a 38.2a 3.07a 0.39b 9.1a 9.1a 0.73b 0.12b 0.21b
Late
Row spacing
37.7a 37.5a 3.28a 1.01a 9.0a 9.2a 0.78a 0.13a 0.24a
20 (cm) 0.49a
8.9a 9.3a 0.78a 0.15a 0.21b
0.85a 0.50a
3.29a 40 (cm) 37.6a 36.5a
aMeans in the same column followed by the same letters are not significant at (PB0.05) by a GLM protected LSD test.
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Table 3
The effects of cultivar, planting date and row spacing on sweet white lupin seed quality and its components on sandy-loam soil in 1992
Oil variables Protein variables
Management factors
BPY SGOC BGOC SOY BOY
SPY TOY
BGPC TPY
SGPC
(mg plant−1)
(t ha−1) (mg plant−1)
(mg plant−1) (mg plant−1) (mg g−1) (t ha−1)
(mg g−1) (mg g−1)
(mg g−1)a
Culti6ar
10.2a 11.1a 1.17b
35.9a 4.28a 0.85a 0.40a
37.5ab
Ultra 2.72a 1.40a
10.8a 11.5a 1.35a
Primorski 37.4a 36.2a 4.62a 3.70a 1.37a 1.18a 0.41a
Planting date
10.5a 11.0a 1.41a
34.9a 4.82a 0.87b 0.42a
36.3a
Early 2.68b 1.40a
1.37a
38.6a 37.2a 4.08b 3.75a 10.5a 11.6a 1.12b 1.16a 0.39a
Late
Row spacing
1.49a
38.1a 36.9a 4.44a 2.97a 10.2a 11.1a 1.20a 0.91a 0.42a
20 (cm)
10.8a 11.5a 1.32a 1.13a 0.39a
1.29a
35.2a 4.46a 3.46a
40 (cm) 36.8a
aSGPC, stem seed protein concentration (mg g−1); SPY, stem seed protein yield (mg plant−1); BPY, branch seed protein yield (mg plant−1); TPY, total protein yield (t ha−1); BGOC, branch seed oil concentration (mg g−1); SOY, stem seed oil yield (mg plant−1); BOY, branch seed oil yield (mg plant−1); TOY, total seed oil yield (t ha−1).
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Table 4
The effects of cultivar, planting date and row spacing on sweet white lupin seed quality and its components on clay-loam soil in 1992a
Oil variables Protein variables
Management factors
BPY SGOC BGOC SOY BOY
SPY TOY
BGPC TPY
SGPCb
(mg plant−1)
(t ha−1) (mg plant−1)
(mg plant−1) (mg plant−1) (mg g−1) (t ha−1)
(mg g−1) (mg g−1)
(mg g−1)
Culti6ar
9.4a 10.1a 1.11a
35.9a 3.25b 0.51b 0.41a
37.5a
Ultra 1.86b 1.56a
9.5a 10.0a 1.19a
Primorski 37.4a 36.6a 4.63a 3.47a 1.50a 1.29a 0.39a
Planting date
9.6a 10.2a 1.41a
36.1a 5.11a 0.82a 0.42a
37.4a
Early 2.25a 1.59a
1.47a
37.5a 36.9a 2.76b 3.08a 9.3a 9.9a 0.89b 0.98a 0.38a
Late
Row spacing
1.61a
37.5a 36.6a 4.23a 2.31a 9.4a 10.1a 1.17a 0.63b 0.42a
20 (cm)
9.5a 10.0a 1.13a 1.17a 0.38a
1.45a
35.9a 3.65a 3.02a
40 (cm) 37.4a
aMeans in the same column followed by the same letters are not significant at (PB0.05) by a GLM protected LSD test.
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In 1991, management factors such as cultivar and planting date had greater effects on main-stem and branch seed oil yield and total seed oil yield than row spacing (Tables 1 and 2). Early seeded lupin increased stem and branch oil yield and total protein yield at all site-years, except for branch oil yield of late-planted plants grown on clay soil in 1992. Primorski had greater per plant seed oil yields for stems and branches but less total seed oil yield per unit area than Ultra (Ta-bles 1 and 2) due to a smaller population for Primorski than Ultra (Ultra (53.8 plants m−2
) vs. Primorski (34.8 plants m−2
) on clay soil, and Ultra (51.8 plants m−2
) vs. Primorski (27.4 plants m−2) on sandy soil). In 1992, early planting re-sulted in 26 and 58% higher stem seed oil yield than late planting (Table 3). Branch seed oil yield increased by 33 and 86%, due to late planting and wider row spacing, respectively. At both experi-mental sites in 1992, management factors did not affect total oil yield (Tables 3 and 4).
Across other management factors (row-spacing and cultivars), early planting increased stem oil yield by 17, 13, 24, and 59% on sandy and clay-loam soils in 1991 and 1992, respectively. Pri-morski had greater branch-oil yields than Ultra at three of the 4 site-years. In 1991, the branch-oil yields per plant of Primorski were 5.5 and 2.1 fold higher than those of Ultra on sandy and clay-loam soils (Tables 1 and 2), respectively, while they were 153% higher on the clay-loam soil in 1992 (Table 4).
3.5. Interrelationships between seed oil and protein
The Spearman’s correlation coefficient (Con-over, 1971) (for seed quality variables) indicated a significant negative association between seed protein and lipid concentrations (r, −0.61; P, 0.001) in 1991. A parallel relationship was present between branch seed oil and protein concentra-tions. The correlation between seed protein and oil yields per plant (r, 0.95; P, 0.001 in 1991 and
Management factors affected the protein and oil concentrations of lupin seeds. Both protein and oil concentrations were affected by planting date. Planting date generally had a much greater effect on seed-protein and oil yields than row width. In general, row width had little effect. Seed protein levels were more sensitive to planting date than seed oil levels, and early planting often de-creased seed protein concentration. This could have been due to changes in either oil or carbohy-drate levels in the seeds. The occasional increases in seed oil levels due to earlier planting suggest that this was a part of the cause for decreases in protein levels. However, the fact that these oc-curred much less frequently than protein level decreases suggests that increases in carbohydrate level accounted of most of the decreases in protein. Our data indicate that branch and stem seeds are about equally sensitive to management factors in terms of changes to oil and protein concentrations. Comparisons of the stem and branch protein yields showed that the branch protein yield was more sensitive to management factors at both sites in 1991. Thus, the protein yield increases were largely due to branch protein yield increases.
The increases in the seed lipid yield per plant by pods borne on the main stem, due to clay-soil, early-planting, the 20 cm row-width and Ultra in 1991, versus the alternate state of each factor, were 25, 15, 10 and 43%, respectively; the corre-sponding values for the differences in seed protein yield per plant were 3, 21, 13 and 37%. However, some of these relative increases were not present in the cooler and wetter year of 1992.
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creased both protein and oil yields in 1991, espe-cially for the cultivar Ultra.
Shaw and Liang (1966) and Stone and Turker (1969) reported maximum protein concentrations when soybean plants were water stressed during pod filling. The moisture stress that occurred dur-ing pod filldur-ing in 1991 may have lead to higher protein concentrations in the seeds of white lupin plants grown on sandy-loam soil, which would have had less moisture holding capacity than the clay-loam soil. The cooler weather (with averages 1.3, 1.4 and 2.8°C less for May, June and July, respectively, than mean temperatures for corre-sponding months in 1991) and adequate rainfall in 1992 resulted in more moisture in the soil for crop growth and development. This lead to lower seed protein concentrations in 1992 (37.4 and 36.1% on the main and secondary branches, re-spectively) than for 1991 (38.6 and 37.5% on primary and secondary branches, respectively) (Tables 1 – 4).
The negative and significant correlation (r,
−0.61; P, 0.01) between lupin seed protein and oil concentrations in 1991 agrees with the findings of other researchers (Dhawan et al., 1972;
Udaya-seekhara and Rao, 1981; McKendry and
McVetty, 1985) working with other oil crops. This negative relationship indicates that these two quality traits are inversely related in sweet white lupin. Thus, concurrent selection for increased seed-oil and protein concentrations would proba-bly be difficult, as any attempt to select for in-creased concentration of one character would probably depress the other.
5. Conclusions
Management factors affected the protein and oil concentrations of lupin seeds. In general, row width had little effect. Both protein and oil con-centrations were affected by planting date. The better management practices for production of protein or oil by sweet white lupin in eastern Canada involve early planting. Choice of cultivar is clearly important. In addition, under these cli-matic conditions sweet white lupin does somewhat better on heavier than on lighter soil for both
protein and oil production. Protein and oil yield by branch seeds were much more affected by management factors and climatic conditions than they were for stem produced seeds. The negative association between seed protein and lipid con-centrations indicates that it may be difficult to improve the two quality traits concurrently. How-ever, the positive and significant relationships be-tween seed lipid and protein contents (P, 0.01) are indications that both seed oil and protein yields of sweet white lupin crops grown in short season areas, can be concurrently improved through suit-able crop improvement methods.
Acknowledgements
The authors wish to acknowledge the financial assistance of the Natural Sciences and Engineer-ing Research Council of Canada and the Cana-dian International Development Agency who jointly funded an associateship for the first au-thor. Appreciation is extended to the Ondo State University (Nigeria) for permitting the first author to participate in the research program.
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