Chicory and Jerusalem artichoke productivity in different areas of Italy, in relation to water availability and time of harvest

Inulin is an important polysaccharide synthesised by different crops, which, in the EU has been included in the system of sugar quotas since 1994. Currently, one of the major problems of the agro-industry is the need to extend the length of the sugar crop harvest season. It was therefore decided, also in relation to the increased demand for inulin, to study the two main inulin producing crops in Italy (chicory and Jerusalem artichoke), to verify yield and quality potential and stability in relation to some important agronomic factors such as irrigation and time of harvest. The work was conducted in 1999 and 2000 in four areas of Italy (Udine, Rovigo, Bologna and Bari). The effects evaluated were time of harvest (3 for chicory and 2 for Jerusalem artichoke) and irrigation system (evapotranspiration replacement and dry regime, with irrigation applied only when strictly necessary) on the production of storage organs, sugars and inulin in the two crops. The highest chicory root yield was in Bologna, with an average production of 65.6 t ha -1 (fresh weight), compared to Rovigo (54.4 t ha -1 ), Bari (46.5 t ha -1 ) and Udine (38.7 t ha -1). For final tuber yield in Jerusalem artichoke, Bari was the most productive environment with an average of 80 t ha -1 , followed by Bologna (61 t ha -1 ) and Udine (55.5 t ha -1 ). However, when this crop is whole-plant harvested (stalks and tubers) at pre-flowering, Bologna, with high stalk yields (58.7 t ha -1) appeared to be the most suitable environment. This type of harvesting was also shown to be more productive in terms of sugar and inulin yield. The total sugar content in the different organs analysed (roots, stalk and tubers) was always higher in Udine compared to Bologna, for both crops. Lastly, the length of the inulin chain (average degree of polymerisation [DP]) diminishes with the delaying of the harvest in both crops. The Bologna area had the highest potential in terms of chicory root production, while for the tubers yield of Jerusalem artichoke, the Bari environment was the most productive. But, when Jerusalem artichoke is instead considered as a crop for whole-plant harvest (stalks and tubers), Bologna, with a very high stalk yields, becomes the most suitable area. The highest sugar content in roots, stalks and tubers of both crops was found in the Udine tria

Interaction between agronomic and mechanical factors for fiber crops harvesting: italian results. Note I. Kenaf and fiber sorghum.

This paper considers the first steps in some of the production chains of kenaf and fiber sorghum. Effects of agronomic techniques (such as crop density, sowing and harvesting period, and variety) are evaluated. Their influence on biometric characteristics of the crops is studied on the basis of harvesting and first transformation machines. Effects of the interaction between agronomic techniques and machines are considered with respect to the qualitative and quantitative characteristics of the product obtained

Crop yield and quality parameters of 4 annual fibre crops (Hemp, Kenaf, Maize and Sorghum) in the North of Italy

Four fibre crops (hemp, kenaf, maize and sorghum) considered amongst the most suitable for the conditions of Northern Italy were compared in 1995 and 1997, over two irrigation regimes (rainfed conditions and restoration of 100␎Tp) and in two locations (Bologna and Milano). Three harvests were carried out on each crop at different development stages. At each harvest time data on yield and yield components were collected. Sub-samples of stems of each crop and at each harvest time were analysed following the Van Soest method. On average, fibre sorghum proved to be the higher yielding crop. It produced 26.2 Mg ha−1 of total dry matter of which 18.1 Mg ha−1 was partitioned to the stems. Fibre maize produced more total dry matter than kenaf (19.0 Mg–15.7 Mg ha−1) but dry matter accumulated to stems was higher in kenaf (10.8 and 13.4 Mg ha−1). On average, fibre hemp yielded 14.0 Mg ha−1 of total dry matter and 10.9 Mg ha−1 of stems. This result was highly affected by the low hemp production in Bologna in 1995, where unfavourable conditions, in the first phases of cultivation, resulted in a stunted establishment of the crop (18.7 Mg ha−1 of total dry matter in Milano and only 8.3 Mg ha−1 of total dry matter in Bologna). On all crops, irrigation produced a slight increase in total biomass (7€and in stem dry matter (9€compared to the rainfed condition. In both locations, yield increase due to irrigation was larger in maize and kenaf, than in hemp while, in 1995, it caused a severe lodging on sorghum. The four species proved to be different for growth rates, patterns of development and particularly for cellulose, hemicellulose and lignin content of stems. Cellulose content varied between 56–66␘f stem dry matter in hemp, 46–57␒n kenaf, 35–45␒n maize and 39–47␒n sorghum. As harvest time was delayed, cellulose content tended to increase for hemp and kenaf while it decrease for sorghum and maize. Hemicellulose content of hemp and kenaf stems varied between 16–19°while it varied between 26–29␒n sorghum and maize. Hemicellulose content decreased with irrigation and with delay in harvest time. Lignin content in hemp stem ranged between 8 and 13°it was 6.9␒n kenaf and maize, and ca 8␒n sorghum

The effect of transient and continuous drought on yield,photosynthesis and carbon isotope discrimination in sugar beet (Beta vulgaris L.)

Stable carbon isotope discrimination (Δ13C), photosynthetic performance (A), dry matter accumulation (DW), and sucrose yield (Ys) of sugar beet were evaluated in a glasshouse experiment under transient (TS) and permanent (PS) water stress. A was significantly reduced under drought, to an extent depending on stress duration. The reduced A was strictly associated with a low DW and Ys, the later being 42% lower in PS than control plants (C). Restoring water steeply increased A and the associated leaf traits (RWC, leaf water potential etc.), but the increase of Ys was negligible. Therefore, the negative effects of severe water stress in the early growth period, though reversible on gas-exchange and most leaf traits, can drastically reduce Ys of sugar beet. Furthermore, A seems not to be effective in predicting sucrose accumulation, although it was very effective in detecting the occurrence of plant water stress. The A/C i model was used to assess the photosynthetic adjustments to continuous or transient drought by calculating the photosynthetic parameters Vcmax and Jmax and then compared with Δ 13C. Mesophyll conductance (gm) was estimated by comparing Δ13C measured on soluble sugars and gas-exchange data. This approach confirmed the expectation that gm was limiting A and that there was a significant drop in [CO2] from the substomatal cavities and the chloroplast stroma both in favourable and drought conditions. Therefore, the carbon concentration at the carboxylation site was overestimated by 25-35% by conventional gasexchange measurements, and Vcmax was consistently underestimated when gm was not taken into account, especially under severe drought. Root Δ13C was found to be strictly related to sucrose content (brix%), Ys and root dry weight, and this was especially clear when Δ13C was measured on bulk dry matter. By contrast, leaf Δ13C measured in soluble sugars (Δs) and bulk dry matter (Δdm) were found to correlate weakly to brix% and yield, and this was not surprising as the integration time-scale of leaf Δs and Δdm were found to be shorter than that of root Δ13C in bulk dry matter. The effect of water stress on diffusive and biochemical limitations with different integration times ranged from 1 d (leaf Δs) to more than 1 month (root Δdm)