Le parole della crisi, le politiche dopo la pandemia. Guida non emergenziale al post-Covid-19

Lo scorso 11 marzo, l'Organizzazione Mondiale della Sanità ha dichiarato il Covid-19 una pandemia. Molti paesi hanno conseguentemente adottato o inasprito le misure di contenimento della mobilità e la sospensione delle attività produttive. Inevitabilmente, la crisi ha coinvolto la sfera economica, quella sociale, il mondo culturale e l'ambito politico-istituzionale, in alcuni casi esacerbando tendenze che erano presenti in nuce nella trama delle relazioni intersoggettive, altre volte lacerando le aspettative, i valori e le percezioni sui quali ciascuno di noi, e la comunità nel suo complesso, definisce e articola la propria esistenza. Il CEST - Centro per l'Eccellenza e gli Studi Transdisciplinari, come associazione di studenti, dottorandi e giovani ricercatori, con diversi background, propone un volume che analizza, in chiave transdisciplinare, la pluralità dei possibili effetti dell'emergenza in corso e indica alcune linee direttrici per immaginare la sua gestione nei prossimi mesi, mediante un approccio specifico e originale: il libro è infatti il frutto della collaborazione tra giovani studiose e studiosi e figure autorevoli del dibattito culturale italiano e internazionale

Propagación vegetativa de Petiveria alliacea L. var. alliacea

The aim of this work was to evaluate the proliferation of Petiveria alliacea L. var. alliacea by live stakes in the agroecological conditions in the northwest of Corrientes Province, determining its most appropriate propagation time, substrate and the use of rooting promoters. The analyzed  factors were type of live stake (levels: terminal stakes and intermediate stakes), type of substrate (levels: sand and commercial mixture) and treatment with plant growth regulator (levels: with and without growth regulator). The test was repeated in autumn, winter and spring. Once the results of each test was obtained, the corresponding analysis of variance was carried out after verification of normality and a significance test (Tukey's test at a level α = 0.05) using Infostat software. Statistical analysis was performed for each staking date, main factors were evaluated separately, as well as possible interactions. It was concluded that multiplication by  live  stakes is  a fast  and efficient method of asexual propagation of Petiveria alliacea L. var. alliacea. Intermediate live stakes were the most convenient ones for successful rooting and subsequent sprouting. The treatment of live strakes with ANA would not be necessary while the cutting is carried out in spring and autumn, but it would be convenient  to use it if it is expected to propagate this species through live stakes in winter. The highest percentages of rooting and sprouting were obtained in sand substrate.El objetivo del presente trabajo fue evaluar la multiplicación de Petiveria alliacea L. var. alliacea mediante estacas en las condiciones agroecológicas del noroeste de la Provincia de Corrientes determinando su época de propagación más adecuada, sustrato más adecuado  y el uso de promotores de enraizamiento. Fueron analizados los factores: tipo de estaca (niveles: estacas terminales y estacas intermedias), tipo de sustrato (niveles: arena y mezcla comercial) y tratamiento con regulador de crecimiento vegetal (niveles: con y sin). El ensayo fue repetido en otoño, invierno y primavera. Una vez obtenidos los resultados de cada ensayo se procedió a realizar su  correspondiente análisis de la variancia previa verificación de la normalidad y test de significancia (Test de Tukey a un nivel = 0.05) empleándose el software Infostat. El análisis estadístico se realizó para cada fecha de estaqueo, y se evaluaron los factores principales por separado, así como las posibles interacciones. Se concluyó que la multiplicación por estacas es un método rápido y eficiente de propagación asexual de Petiveria alliacea L. var. alliacea. Las estacas intermedias fueron las más convenientes para obtener éxito en el enraizamiento y posterior brotación. El tratamiento de las estacas con ANA no sería necesario mientras el estaqueo se realice en primavera y otoño, pero sí sería conveniente cuando se desee propagar esta especie mediante estacas en invierno. El sustrato arena fue donde se obtuvieron los mayores porcentajes de enraizamiento y brotación

Spring frost effects on 30 sweet cherries varieties grown in North Italy

After a spring frost occurred in second half of March 2008, with temperatures below 0°C for 8 days consecutively and an absoluteminimum of -5.5°C, a lot of observations have been made on the sweet cherry flowers damages. In three different orchards “Italian palmetta”trained on grassing ground soil, the percentage of the flowers killed by frost, was detected and recorded considering the different genotypesand flowers height from the ground. Furthermore, in one orchard only it was possible to find relationship between flowering stage and frostdamage. The results clearly confirm our previous works about the highest mortality of the flower in the upper part ( > 1.50 m) of the canopyand in the full bloom open flowers. So, in this area, the easiness of agronomic operations, like pruning and, especially, fruit harvest, due to thecrown proximity to the ground, is cancelled by the frequency of spring frost