J. Papineau

Seed yield and yield stability of determinate and indeterminate autumn-sown white lupins ( Lupinus albus ) grown at different locations in France and the UK

The seed yields and maturity dates of an indeterminate cultivar (Lunoble) and a determinate line (CH304/70) of Lupinus albus L. were measured at three locations in France (Lusignan, Dijon and Gotheron) and at Rothamsted, UK, in 1989/90 and 1990/91. Different combinations of sowing dates, plant densities and irrigation treatments were tested at some sites. Averaged over all sites, CH304/70 yielded more than Lunoble (3.26 v. 2.98 t/ha) but there were significant genotype x location interactions for yield and date of maturity. Both genotypes gave similar yields at the three locations in France (3.13 and 3.06 t/ha, respectively) (.)

Genetic and environmental variation in architecture and yield components in determinate white lupin (Lupinus albus L.)

SummaryDeterminate architecture is of great interest for lupin production in Europe but the extent of genetic and environmental variation in the structure and yield of determinate lupins must be evaluated. Forty-three genotypes of determinate autumn-sown white lupin were studied in four environments in France in 1991/92 and 1992/93. Wide variation was observed for phenological (dates of mainstem and branch flowering, date of end of flowering and date of maturity), morphological (numbers of branch orders, branches and leaves) and seed characters (seed yield, mean seed weight, number of seeds/m2). Both genetic and environmental effects contributed to the observed variation. Heritabilities were high for all characters, and the interaction between genotype and location effects was low. There were significant positive correlations of flowering dates with vegetative plant development including the number of branches, number of leaves and number of branch orders. Seed yield and phenological and archtectural characters were significantly correlated. Distribution of yield on the vegetative orders showed important variations according the genotype, and the variations were related to variation for the architecture. There are possibilities for yield improvement using morphological characters in determinate autumn-sown lupin.

Dry matter and nitrogen accumulation in indeterminate autumn-sown white lupin (Lupinus albus) cv. Lunoble

Abstract The dry matter and nitrogen accumulation of autumn-sown white lupin ( Lupinus albus L.) cv . Lunoble was studied in four seasons at different plant densities. Total net dry matter accumulation was more than 1500 g m −2 in most conditions, and net nitrogen accumulation reached 30 g m −2 at harvest time. The mainstem and first-order branches contributed most to final dry weight and final pod weight. The distribution of dry matter among branch orders was influenced by year and density ; the production of the mainstem increased and the production of upper orders decreased at the high density. Leaf area index reached 5.5 at its maximum. Each branch order sequentially developed a LAI of 2, intercepting the major part of the incident light and shading the previous one. The duration of a LAI above 2.5 was positively correlated with the total dry matter production. Pod weight was not correlated with total dry matter. During pod filling, the leaf dry matter and nitrogen decreased, possibly indicating direct mobilization of dry matter from leaves to pods.

Genetic inheritance of proportion of pod walls and other yield components in white lupin

The present study was conducted toinvestigate the genetic inheritance of podcomponents in spring-sown white lupin. Ananalysis of the genetic parameters ofproportion of pod walls and related podcomponents should be helpful to define aselection strategy in the future lupinbreeding programs. Two mating designs wereused, a complete diallel, and a halfdiallel, without reciprocals and withoutselfing. The parental lines covered therange of genetic variation for theproportion of the pod walls available inthe white lupin collection from INRA,France. Diallel analyses were carried outvia Griffing (model I and II) andHayman methods. Proportion of pod walls,seed weight per pod and mean seed weightshowed a mainly additive inheritance.Narrow sense heritability was higher forthe proportion of pod walls than for theother pod components. The correlationbetween general combining ability (GCA) andparental phenotypic values was high forproportion of pod walls. This suggestedthat mean parental performance could be auseful indicator of mean cross performancefor the proportion of pod walls in whitelupin. For pure line breeding, theestimates of GCA values showed thatEgyptian accessions would be valuableparents. Breeding for reduced proportion ofpod walls may be a way of improving seedyield.

Dry matter and nitrogen accumulation during pod wall development of white lupin genotypes differing in proportion of pod walls

Pods of white lupin are characterized by a high proportion of pod walls in the pod mass at maturity. Genotypic variation in pod wall thickness at maturity and in proportion of pod walls has been described in this species. The objective of this study was to describe the pod and seed development in two ecotypes and one cultivar of spring-sown white lupin differing in proportion of pod walls, and to estimate the precise stage of development when the differences in pod wall dry matter among genotypes are first observed. The nitrogen content was also determined during the pod development of three genotypes. LA356, E084 and Lublanc were grown in the field in the UK and France in 1998 and 1999. The duration of pod and seed development was similar among genotypes and environmental conditions. Proportion of pod walls by dry weight at maturity were 0·21–0·23 for LA356, 0·27–0·28 for E084 and 0·30 for Lublanc. The ecotype with the lowest proportion of pod walls accumulated less dry matter in the pod walls than those with the highest proportion. Variation in pod wall dry matter per seed between genotypes was observed early during the pod development (300°C days from flowering) and it was maintained during all pod development. No significant differences were observed for the total nitrogen content at maturity among genotypes with high and low proportion of pod walls.

Yield and yield components of indeterminate autumn-sown white lupin (Lupinus albus) cv. Lunoble

Abstract The seed yield and its components were analysed in the autumn-sown white lupin cultivar Lunoble across a range of 19 cropping conditions. Under irrigation, year had a major effect and plant density only slightly affected the total seed yield but changed the contributions of the pods on different branches. Under rainfed conditions, both sowing date and plant density significantly influenced seed yield, the average seed yield being higher than under irrigation. The yield was significantly correlated with the mean seed weight and with the number of seeds per m 2 . Under irrigation, the yield was strongly correlated with harvest index while, under rainfed conditions, biological yield was the main factor limiting seed yield. Harvest indices were higher without than with irrigation. The seed yield on the mainstem was negatively correlated with the total dry weight of the branches at maturity. The intraplant competition and the effects of the environment, especially the plant density and the water status, on the yield and on yield stability are discussed in relation to the architecture of the autumn-sown white lupin.