Soil fertility requirements of root chicory (Cichorium intybus var. sativum): a review

Abstract

Root chicory is mainly grown in Belgium and the Netherlands with production also elsewhere in Europe, India, and South Africa. The world’s crop is worth an estimated US$56.04 million. India and South Africa focus on supplying root chicory to the blend coffee industry. Only limited and variable information is available on the fertilizer requirements of root chicory. Most studies on nitrogen (N) report that chicory in cooler, temperate regions requires 40–75?kg?N/ha compared to 200?kg?N/ha in warmer areas. Recommended rates for phosphorus (P) range from 0 to 69?kg?P/ha. Poor responses to potassium (K) are reported with recommended rates from 0 to 190?kg?K/ha. Application rates for sulfur (S) of 10–30?kg?S/ha have been suggested. Suitable micronutrient requirements and soil acid saturation and pH values for root chicory have not been published. To establish crop norms a concerted effort is needed to quantify the fertilizer use of root chicory.     

Effect of moisture stress on Nitrate Reductase Activity (NRA) in PEA (Pisum sativum L.) [C3] and sorghum (Sorghum vulgare Pers.) [C4] plants

Nitrate reductase activity (NRA) was studied in pea, a C₃ plant, and sorghum, a C₄ plant, at various stages of growth and development. Influence of moisture stress and nitrogen application was also observed since these factors have profound influence on growth and development.

In pea, NRA was maximum at pod maturity stage and minimum at flowering stage. In sorghum plant there was gradual increase in NRA upto grain formation followed by a fall in activity at maturity.

Nitrogen treatment as nitrate and ammonia significantly increased nitrate reductase activity over control in both pea and sorghum. Treatment with potassium nitrate was found to stimulate more NRA in pea than with ammonium sulphate. In sorghum, both forms of nitrogen did not differ much in their influence on NRA.

Influence of moisture stress in reducing NRA was more clear in sorghum, a C₄ plant than in pea, a C₃ plant. In general, control plants recorded low NRA in both the crops when compared to nitrogen treated plants except at pod formation stage in pea.     

Pea-oat intercrops are superior to pea-wheat and pea-barley intercrops

Abstract

A three-year field experiment was conducted in Estonia to determine which combinations of pea (Pisum sativum L.) and wheat (Triticum aestivum L.), oats (Avena sativa L.) and barley (Hordeum distichon L.) were most suitable for mixed cultivation and the effect of pea on the yield potential of cereals. The inclusion of pea in cereal seeds and the increasing of its seed density led to substantial decreases in the grain yields of the cereal component. The reason for these decreases was the formation of smaller grains in cereals when intercropped with pea. The inclusion of pea in a cereal crop and the increasing of its seed density led to substantial increases in the protein content of the cereal grains. In barley and oats the increases in grain protein content were the lowest of the three cereals. At the same time, the maximum protein yield per area unit in cereals was obtained from plots of pure crops. In a mix with pea, the amounts of nitrogen consumed by cereals decreased and the protein yield of cereals per area unit were reduced in intercrops. Pea-cereal mixes had an advantage over cereal sole crops with regard to protein yield, due to the pea component. Pea-cereal mixes are particularly suitable for the conditions of organic farming, and should be recommended to farmers, as they ensure a relatively good harvest and high protein yield on soil without nitrogen fertilizers. In conclusion, the study showed that, of the three combinations, pea-oat mixed intercrops gave the highest yield of grain and protein yields.     

The genetics of pea seed storage proteins

The genetics of legumin, vicilin and convicilin, the major seed storage proteins of the pea, are discussed in relation to current understanding of their structure, biosynthesis and evolution.     

Adaptation strategy,germplasm type and adaptive traits for field pea improvement in Italy based on variety responses across climatically contrasting environments

A pea breeding strategy is required to cope with the large climatic variation featuring south-European environments. Thirty-seven recent cultivars bred by 21 European or Australian institutions were grown in two climatically contrasting Italian sites (Lodi, subcontinental; Foggia, Mediterranean), two cropping years per site and two sowing times per year, to define various elements of this strategy. The study assessed: (i) the impact of genotype × environment (GE) interaction due to spatial and temporal factors on the consistency of top-yielding cultivars; (ii) the similarity between environments for GE effects and its implications on adaptation strategies; (iii) the extent of genotypic and GE interaction effects, and the relationship with adaptive responses, for various morphophysiological traits; (iv) the adaptation pattern and the combination of adaptive traits featuring three germplasm types, i.e. European spring and winter types, and germplasm selected in Mediterranean environments; (v) the predicted efficiency of direct and indirect selection procedures for grain yield. The geoclimatic area had a major impact on crop yield (5.15 t/ha in Lodi vs. 2.52 t/ha in Foggia) but tended to affect GE interaction less than time or year of autumn sowing, suggesting to breed for wide adaptation. Top-yielding cultivars as modeled by additive main effects and multiplicative interaction were environment-specific. On average, spring and winter materials outyielded the Mediterranean germplasm but the spring type, characterized by wide entry variation, included most widely- and specifically-adapted top-yielding cultivars. Cold-tolerant spring-type germplasm is preferable to breed for wide adaptation as it may combine high yield potential with adaptation to winter cold and terminal drought and heat stress. Lodging susceptibility, harvest index, onset and duration of flowering, and canopy height at maturity assessed in individual environments showed moderate to fairly high broad-sense heritability on a plot basis (h² > 0.20) and tended to correlation with yield over test environments (r ≥ 0.20). An indirect selection index including harvest index and canopy height exhibited about 20% greater predicted efficiency than direct selection for yield when using one selection environment and could be preferred for early selection stages. Direct yield selection in late selection stages should ideally be performed across 2 years in two environments that contrast for geoclimatic area and time of autumn sowing.     

Identification, pathogenicity and distribution of Penicillium spp. isolated from garlic in two regions in Argentina

A total of 147 samples of garlic ( Allium sativum ) bulbs affected by blue mould were obtained from a variety of agroclimatic districts between December 1999 and February 2000. Penicillium species were identified using both morphological and chemotaxonomic characteristics. Penicillium allii was the predominant species isolated (81·8%) in this survey and the only species proven to be pathogenic on garlic. Other species were isolated much less frequently: P. chrysogenum (13·7%), P. brevicompactum (2·8%), P. phoeniceum (0·9%), P. aurantiogriseum (0·6%) and P. flavigenum (0·2%). Colonies of P. allii could be classified into four morphotypes and their distribution seemed to be influenced by seed trade and agricultural practices. Penicillium allii isolates were grouped into three aggressiveness phenotypes (low, medium and high) based on their ability to cause disease during field trials on susceptible (Fuego INTA) and less susceptible (Castaño INTA) garlic cultivars. The number of surviving plants at 191 days after planting and postharvest bulb weight contributed the most towards aggressiveness modelling.     

Effect of pea plant architecture on spatiotemporal epidemic development of ascochyta blight (Mycosphaerella pinodes) in the field

The effect of pea canopy structure on epidemics of Mycosphaerella pinodes was investigated in four spring pea cultivars (Bridge, Obelisque, Solara and Athos) in two field experiments. These cultivars had similar levels of susceptibility to ascochyta blight and presented different architectural features (branching, standing ability and stem height). Stem height ranged from 77 to 95 cm in 1999 and from 72 to 92 cm in 2000, while leaf area index (LAI) ranged from 3·8 to 5·1 in 1999 and from 3·8 to 4·7 in 2000. Internode lengths varied from 4·6 to 6·0 in 1999 and from 3·8 to 4·7 in 2000. Mean distance between nodes in the canopy (MDN) ranged from 12·2 to 15·3 cm in 1999 and from 11·2 to 13·9 cm in 2000. Canopies with different architecture differed in disease progression on stipules and mainly on pods. The levels of disease on stipules and pods were strongly correlated. Moreover, if disease was considered as a function of stipule height up the stem, large differences in vertical disease distribution were observed between cultivars. Three architectural features acted on disease development: cumulative LAI above the node on which disease was assessed (LAIcum) and large MDN favouring disease development, and large internode length reducing disease severity. Modifying LAI distribution and plant organization could be one way to reduce the impact of ascochyta blight, by direct or indirect effects on environmental and dispersal conditions.     

The use of RAPD technique for the identification and classification of Pisum sativum L. genotypes

Summary The genomic DNAs of 42 Pisum sativum genotypes, representing four wild and cultivated subspecies were used as templates in RAPD reactions. Amplification with eight decamer primers generated 149 polymorphic products. Genetic similarities of RAPD profiles were estimated via a coefficient of Jaccard and then the data were processed by cluster analysis (UPGMA). Each genotype was clearly identified and separated from the others. Our results show that RAPD technology is a rapid, precise and sensitive technique for identification of pea genotypes. However, the phylogenetic relationships within the Pisum sativum, which we tested by bootstrap analysis (Wagner parsimony), must be interpreted with caution.     

Genetics of powdery mildew resistance in pea

The genetics of powdery mildew (Erysiphe pisi) resistance in pea (Pisum sativum) was studied using five isolates of E. pisi in a controlled environment. Resistance was controlled by a single recessive gene in all the pea cvs. included in the study. The same recessive gene controlled resistance to all the five isolates of E. pisi. Tests for allelism showed that resistance in cvs. HPPC-63, HPPC-95, DPP-26, DPP-54, Mexique-4, SVP-950, Wisconsin-7104 and P-6588 is conferred by the same recessive gene. This revised version was published online in July 2006 with corrections to the Cover Date.     

Genetic diversity and relationships among pea cultivars revealed by RAPDs and AFLPs

In order to obtain an overview of the genetic diversity present within the set of pea cultivars released in Germany, 21 cultivars were analysed at the DNA level by random amplified polymorphic DNAs (RAPDs) and amplified fragment length polymorphisms (AFLPs), as well as for agronomic traits. Yield of grain cultivars ranged from 2.95 to 3.87 t/ha. Based on the screening of 60 RAPD primers and 32 Eco RI + 3/Mse I+3 AFLP primer combinations, 20 RAPD primers and 11 Eco RI + 3/MseI+ 3 primer combinations generating polymorphic and distinct fragments were chosen for estimation of genetic diversity. Twenty RAPD primers amplified a total of 314 scorable bands ranging from about 262 bp to 1996 bp. Of these, 175 fragments (55.7%) were polymorphic. Based on these data, genetic similarity (GS) was estimated between 0.80 (‘Lisa’ vs.‘Grapis’) and 0.94 (‘Bohatyr’ vs. ‘Sponsor’; mean GS = 0.88). Eleven AFLP primer combinations led to the amplification of 949 scorable fragments ranging from 43 to 805 bp and of these, 462 (48.7%) were polymorphic. Genetic similarity based on AFLPs was calculated between 0.85 (‘Lisa’ vs.‘Laser’) and 0.94 (‘Bohatyr’ vs. ‘Sponsor’, mean GS = 0.90). Correlation of genetic similarity estimated on RAPDs and AFLPs was estimated at r = 0.79** using Spearman's rank correlation coefficient and at r = 0.84 by the Mantel test, respectively. UPGMA cluster analysis carried out on these data separately for RAPDs and AFLPs and on the combined data reflected, to some extent, pedigree relationships and cophenetic correlations (r = 0.89 for RAPDs, r = 0.88 for AFLPs, and r = 0.93 RAPDs + AFLPs) indicate a good fit of respective clusters to genetic similarity data. The correlation of cluster analyses to pedigree information and the impact on parental genotype selection is discussed.