Effects of early mycorrhization and colonized root length on low-soil-phosphorus resistance of West African pearl millet

Phosphorus (P) deficiency at early seedling stages is a critical determinant for survival and final yield of pearl millet in multi-stress Sahelian environments. Longer roots and colonization with arbuscular mycorrhizal fungi (AMF) enhance P uptake and crop performance of millet. Assessing the genotypic variation of early mycorrhization and its effect on plant growth is necessary to better understand mechanisms of resistance to low soil P and to use them in breeding strategies for low P. Therefore, in this study, eight pearl millet varieties contrasting in low-P resistance were grown in pots under low P (no additional P supply) and high P (+ 0.4 g P pot−1) conditions, and harvested 2, 4, 6, and 8 weeks after sowing (WAS). Root length was calculated 2 WAS by scanning of dissected roots and evaluation with WinRhizo software. AM infection (%) and P uptake (shoot P concentration multiplied per shoot dry matter) were measured at each harvest. Across harvests under low P (3.3 mg Bray P kg−1), resistant genotypes had greater total root length infected with AMF (837 m), higher percentage of AMF colonization (11.6%), and increased P uptake (69.4 mg P plant−1) than sensitive genotypes (177 m, 7.1% colonization and 46.4 mg P plant−1, respectively). Two WAS, resistant genotypes were infected almost twice as much as sensitive ones (4.1% and 2.1%) and the individual resistant genotypes differed in the percentage of AMF infection. AMF colonization was positively related to final dry matter production in pots, which corresponded to field performance. Early mycorrhization enhanced P uptake in pearl millet grown under P-deficient conditions, with the genotypic variation for this parameter allowing selection for better performance under field conditions

Tolerant pearl millet (Pennisetum glaucum (L.) R. Br.) varieties to low soil P have higher transpiration efficiency and lower flowering delay than sensitive ones

Abstract Background and aim In the West African Sahel low soil phosphorus (P) and unpredictable rainfall are major interacting constraints to growth and grain yield of pearl millet. Investigating the relationship between transpiration and final yield under the combined effect of water and P stress is fundamental to understand the underlying mechanisms of tolerance and improve breeding programs. Methods We conducted two lysimeter trials using 1 m long PVC tubes (35 cm diameter) filled with a P poor Sahelian soil mimicking soil profiles to assess grain and stover yield, and water use of 15 pearl millet genotypes grown under different P (no P supply or addition of 1.5 g P tube−1) and water (well watered or terminal water stress) regimes. In experiment 2 transpiration was measured twice a week from tube weight differences, and transpiration efficiency (TE) was calculated as dry matter (DM) produced per kg of water transpired. Results Low soil P delayed flowering, and more so in sensitive genotypes. Later flowering of genotypes sensitive to low P made them more sensitive to terminal water stress. Under P limiting soil, genotypes tolerant and sensitive to low P used similar amounts of water (19.8 and 21.7 kg water plant−1, respectively). However, tolerant lines transpired less water prior to anthesis (8.8 kg water plant−1) leaving more water available for grain filling (11 kg water plant−1) while sensitive lines used 14.4 kg water plant−1 pre-anthesis, leaving only 7.2 kg water plant−1 for grain filling. Low soil P decreased grain yield by affecting seed size at harvest and its damage during seed filling overrode the effect of seed size at sowing. Grain yield was positively correlated with water extracted after anthesis. TE was enhanced by P supply, especially in sensitive lines, and TE was higher in tolerant than in sensitive genotypes under low soil P. Conclusions Pearl millet plants tolerant to low P were more resistant to the delay of flowering caused by low P soil and they presented higher transpiration efficiency. The pattern of transpiration was important to cope with terminal water stress under different levels of P availability. Higher transpiration after anthesis, resulting from conservative water mechanism pre-anthesis (higher TE) and possibly by a shorter delay in flowering under low soil P, enhanced grain yield

Towards understanding the traits contributing to performance of pearl millet open-pollinated varieties in phosphorus-limited environments of West Africa

Aims Pearl millet [Pennisetum glaucum (L.) R. Br.] open-pollinated varieties, which are the predominant cultivars, have never been systematically evaluated for adaptation to low-soil phosphorus (P), a major constraint on pearl millet production in West Africa (WA). Methods We evaluated grain yield (GY), flowering time (FLO), harvest index (HI), and residual grain yields (RGY) of 102 open-pollinated varieties from WA under low-P (−P) and high-P (+P) field conditions in six environments of WA. In addition, PE-related traits of the varieties were evaluated at early growth stage in a pot experiment. Results Significant genetic variation was observed for GY, FLO, HI and PE-related traits. P-efficient varieties had higher yield under −P conditions. Varietal performance under −P varied across environments depending on FLO, relative flowering delay under −P (FD) and RGY measured in the field. Low-P-susceptible varieties had higher FLO, lower HI than low-P-tolerant varieties. Response to direct selection under −P field conditions was 20.1 g m−2, whereas indirect selection response under +P was 16.3 g m−2. Conclusions Selection under −P field conditions while taking into account seasonal variations for FLO, FD and PE is expected to be important for improving GY specifically targeting −P environments in WA

Interaction between oxprenolol and indomethacin on blood pressure in essential hypertensive patients.

A double-blind, cross-over study in 16 patients with essential hypertension was carried out, to evaluate any possible interference by indomethacin, a known prostaglandin-synthetase inhibitor, with the antihypertensive effect of oxprenolol, a non-selective beta-adrenoceptor blocking agent. Both indomethacin and oxprenolol, as well as the two drugs combined, inhibited plasma renin activity; no change was found in urinary sodium excretion or body weight. Oxprenolol alone caused a highly significant decrease in the systolic ( - 10.4 mmHg, p less than 0.001), diastolic ( - 7.4 mmHg, p less than 0.001) and mean ( - 7.7 mmHg, p less than 0.01) blood pressures, whereas indomethacin did not influence blood pressure. When the two drugs were given in combination, blood pressure decreased (systolic: - 5.9 mmHg; diastolic: - 4.0 mmHg; mean: - 4.6 mmHg), but the changes induced in blood pressure were reduced by about 50% when compared with those in the oxprenolol alone period. The data show that indomethacin seems to interfere with the antihypertensive effect of oxprenolol, by an action which may be due to the inhibition of prostaglandin synthesi

Dynamics of soil microarthropod populations affected by a combination of extreme climatic events in tropical home gardens of Kerala, India

Climate change is predicted to increase drought and flooding events in the coming decades, especially in the tropics; we need to understand the short-term responses of plant community and soil microarthropods populations to these extreme events.Yet most of our current knowledge on this comes from manipulative studies in temperate regions. The present study reports the impact of a severe summer drought followed by a catastrophic flood in 2018 on soil microarthropod density and biological soil quality across 25 tropical home gardens. Drought reduced the density of organisms six-fold and flooding caused a further threefold reduction. Biological soil quality in the home gardens that were not flooded was restored during the monsoon season but this was just partially possible for microarthropod population size. Three months after flooding, the microarthropod groups encountered were generally able to re-establish their population to the condition prior to flooding. However, none of the group recovered to the mean seasonal values. The severity of previous drought seemed to have overridden any possible adaptation to annual summer water scarcity. Plant species richness in home gardens played a key role towards mitigation and possible resilience to disturbance of these ancient agroecosystems. The capacity of the soil microarthropod communities to recover over the long term after extreme climatic events and its relevance to maintaining ecosystem functions and services in home gardens through soil fertility warrant further investigation

Giuseppe Maria Bondigli. Giurista e uomo di stato nell’età delle riforme (1691-1763)

Giuseppe Maria Bondigli (Montalbano di Zocca1691-Modena 1763) è uno dei più significativiprotagonisti dell’età delle riforme a Modena. Dopogli anni dell’infanzia e dell’adolescenza trascorsi aMontalbano di Zocca, completò gli studi a Modenapresso lo Studio Pubblico San Carlo dove conseguìnel 1715 la laurea “in utroque iure”.Giurista di vaglia, divenne uno degli uomini di fiduciadel duca Francesco III. Numerosi e delicati gliincarichi a lui affidati, fino alla nomina a Segretariodi Stato (1757). Si segnala per l’istituzione, asue spese, delle cattedre di Diritto Criminale(1757) e di Diritto Pubblico (1763) e per la riformadell’Avvocatura dei Poveri (1759). Fondamentalel’impegno per la razionalizzazione della legislazioneestense, preludio alla promulgazione, dopo la suamorte, del Codice Estense (1771)

Research strategies to catalyze agroecological transitions in low- and middle-income countries

Governments are updating national strategies to meet global goals on biodiversity, climate change and food systems proposed in the Convention on Biological Diversity post-2020 framework and agreed at the United Nation’s Climate Change Conference (COP26) and Food Systems Summit (UNFSS). This represents a unique and crucial opportunity to integrate and accelerate food system actions to tackle interconnected global challenges. In this context, agroecology is a game-changing approach that can provide the world’s growing population with nutritious, healthy affordable food, ensure fair incomes to farmers and halt and reverse the degradation of the natural environment. Here, we explore agroecological transition pathways in four case studies from low- and middle- income countries and identify catalysts for change. We find that enabling policy and market environments, participatory action research and local socio-technical support each plays a critical role in stimulating transitions towards agroecology. We propose strategies and priorities for research to better support agroecological transitions using these catalysts of change as entry points. Engagement of governments, private sector, civil society, farmers and farm workers in this research agenda is essential

Anagrelide in Essential Thrombocythemia: a retrospettive study”

COMUNICAZIONE ORALE HAEMATHOLOGICA, (ABSTRACT) VOL 88 (SUPPL) N.RO 15