Ileana Gatti

In vitro tissue culture in breeding programs of leguminous pulses: use and current status

Legumes represent a vast family of plants including more than 600 genera and more than 13,000 species. Among them, the term “pulses” refers only to dried seed crops, excluding those grown mostly for oil extraction (like soybean), where dried peas, edible beans, lentils, chickpeas, cowpea, mungbean, blackgram and pigeonpea are the most common cultivated ones for human consumption due to their high nutritional value. They also have the ability of fixing nitrogen into the soil with symbiotic bacteria, which reduces the need for chemical fertilizers in crop rotations. Conventional breeding methods for pulses are laborious and time-consuming before the release of new genotypes. Thus, alternative biotechnological approaches may be advantageous in this area. Tissue culture, plant regeneration strategies, gene transfer and plant transformation are studied in these pulses. Also, anther, microspore, embryo and ovary culture and their opportunity of application in these pulses are discussed.

Early selection of elite plants in Asparagus

In order to establish an efficient selection criterion the variability in three asparagus populations was evaluated defining the most important yield components and analysing its evolution along three growing seasons. The yield components, coefficient of variation (CV) and the proportion of plants contributing to 80% of the total yield were estimated. The elite plants were selected by mean of total yield and clusters techniques. Multiple regression showed that spear number (SN) and spear weight (SW) were the most important yield components. In every population, total yield (TY) and SN showed the highest values of CV, independently of sex. 69% of the plants contributed to the 80% of the total yield in the first year while in the second and third year the contribution was 57%. At the end of the third year, 17 plants were selected by the average of the total yield and 43 by clusters. It is suggested to select for SW in the first year, reducing in 68% the experimental material. In the second year, the selection for SN would reduce to 5% the plants to evaluate for total yield in the third year. In this way the selected plants are the same but the number of plants to evaluate is dramatically reduced along the years, therefore facilitating the breeders work.

Evaluation of seven asparagus populations ( Asparagus officinalis L.)

The materials of asparagus (Asparagus officinalis L.) that growers have in use are imported by seed dealers and have been selected according to overseas markets requirements. With the aim of selecting proper parents to use in a breeding program, seven populations of Asparagus officinalis (P1 to P7), all rised as white asparagus, were tested during 1993 and 1994, at the Experimental Field of the Facultad de Ciencias Agrarias (Universidad Nacional de Rosario) placed in Zavalla, Santa Fe, Argentina. The evaluation was made on individual plant in a 40 days of harvest period. ANOVA and a cluster analysis were made. In order to improve total and marketable yield, P1, P2 and P3 should be used as females regarding that these ones also have high spear number. To improve spears weight and diameter as well as late production, P5 and P7 are recommended as males, but it should be considered that P5 has a better yield performance.

Selección de progenitores en espárrago

The principal aim of this experiment was to ascertain what the variables are which best explain the variations among individuals within the populations of asparagus which originates from the cultivar Argenteuil and as a result select better plants to form new populations. The test, using 1,280 plants, was carried out at he experimental farm in the Facultad Ciencias Agrarias de la Universidad Nacional de Rosario, Santa Fe, Argentina, in 1996. During 1997 and 1998 the number of spears per plant (TU), the mean weight of spears (PM), mean diameter of spears (DI) total yield (RE), marketable yield (RM), days to first harvest (DAC), number of stalks (NUTA), plant height (ALT) and fresh weight of the fern (MASAV) were measured. According to an analysis of the principal components, the variables RE, RM, PM, DI and TU were responsible for 60% of the variation that exists within the population evaluated.

Analysis of variability and phylogeny in pisum (Pisum spp.) using digital phenotyping and morphological traits

Plant phenotyping links genomics with plant ecophysiology and agronomy. It is usually performed by non-destructive, automated and image-based technology and generates information for efficient and searchable digital characterization of crop that can be performed during routine, periodical regeneration of accessions in germplasm collections. In the present work, ninety-two accessions of Pisum from different species and subspecies were studied during 2015 and 2016. Size and colour traits were measured using digital images from a Samsung CLX 3300 scanner and analysed with appropriate software; also seed weight, plant height and days to flowering were measured. Highly significant differences between accessions and species and subspecies for all these traits were found. When distances among species and subspecies are calculated, P. sativum subsp. sativum showed the greatest distance with P. fulvum (8.02) followed by P. abyssinicum (7.13); while the smallest distance was found between P. fulvum and P. sativum subsp. transcaucasicum (3.16). A Neighbour-joining tree with a cofenetic r of 0.985 was obtained. Seed and pod characteristics as colour parameters and size, obtained by digital phenotyping, have proved to be suitable markers for genetic diversity evaluation and they are useful in evolutionary analysis, allowing the discrimination of the main wild and cultivated species in the genus Pisum.